Abstract:
A system for sketching, illustrating, drawing or painting likeness compositions such as canvas oil paintings from source images includes a set of increasing size reusable overlayable source image grids with image composition frames used with corresponding destination canvas grid patterns, allowing a consistent grid pattern for all canvas sizes by using predetermined grid dimensions for each canvas size. The image grid patterns may be affixed to clear plastic sheets or may be software-generated patterns. This combination greatly simplifies the use of grids in artwork and provides low-cost timesaving methods to draw accurate perspective. The system includes a unique canvas grid ruler for simplifying generation of canvas grid lines and in some embodiments canvases are pre-printed or backside-shadowed with appropriate canvas grid patterns and labels.

Description:
PRIORITY CLAIM 
     This application claims the benefit of U.S. Provisional Application No. 60/168,462 presently bearing a filing date of Dec. 2, 1999 but believed entitled to a date of Nov. 26, 1999 when mailed by certified mail. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to methods and apparatus useable in the fields of art and graphics. In particular the preferred embodiment of this invention accurately creates a likeness of a source image such as a photograph onto a destination base such as a painting on canvas. 
     BACKGROUND 
     Over the past centuries mankind has performed drawing and painting for expression of experiences, communication, documentation, and cultural art. In many cases it has been desirable to generate works of art with accurate shapes and accurate perspective representations. The use of gridding or “squaring” has become commonplace for beginning art students as well as many professional artists for creating a likeness with accurate perspective and shape. In its linear form, gridding involves subdividing a source image into a number of squares that are individually relatable to destination squares usually of a different size drawn upon the destination base such as a canvas, well known in the field of art. In the initial steps of creating a drawing or painting the general outlines of the image in each square are translated into each corresponding destination base square, sometimes including shading details. Any square within finer detail regions may be subdivided into smaller squares, for example four, in order to facilitate accurate detail portrayal onto the destination base or canvas. The final work of coloring the drawing is then performed, typically without further need of grids in that phase. 
     Prior art includes a manual process of inking or penciling a grid pattern of equally spaced parallel lines and a pattern of normals, typically forming squares, onto the source image, and calculating and inscribing a corresponding grid pattern upon the destination base or canvas. Drawing a representation of the source image from each cell of the source grid pattern into each corresponding destination base cell allows accurate relative positioning of the contents within the image cell-by-cell, leading to accurate perspective, shape, and three-dimensional representations. 
     Art and drawing texts, for example, Smith et al, An Introduction to Art Techniques, 1995 describe the process of manual gridding which involves time-consuming measuring and scaling of the original source such as a photograph, and carefully drawing horizontal and vertical grid lines, dividing the desired image area into an array of square cells. The artist then calculates and marks all four edges of the destination base or canvas and later constructs interconnecting graduation lines to form intersecting row and column lines that form a grid pattern of cells to correspond, one-to-one, with the grid previously drawn onto the source image. Typically the destination canvas is larger than the source, but may be of similar or smaller size. The rows and columns are labeled on image grids and canvas grids numerically or alphabetically or both. 
     The aspect ratio height/width for rectangular canvas shapes must be similar for source and destination in order to provide a full and complete linear representation onto the destination base with respect to the source. Artists are taught to individually measure and draw these grid patterns, which is a laborious, tedious, and time-consuming process that can involve mistakes and require erasures. Oftentimes an artist grids an image, then grids the canvas only to find that his/her desired composition is not correctly covered with the grid pattern, and must erase labels and/or grid lines and construct them again. 
     Artists are faced with confusing geometric calculations involving image size and shape, canvas size and shape and magnification, particularly in view of the wide variety of canvas sizes and shapes or aspect ratios. Many drawing textbooks suggest enlarging a source picture on a copy machine prior to gridding. All of these variables often cause artists to compromise their composition area and position due to the complexities of gridding and preparing for drawing. 
     No prior art known to the inventors simplifies the process of composing and drawing a likeness of an image by framing and adjusting the composition on the source while also reducing the complexity of the gridding process of the source and the destination base or canvas in accordance with the present invention. 
     SUMMARY OF THE INVENTION 
     The preferred embodiments of the present invention provide systems, guides and methods for greatly facilitating the process of gridding a photograph or other image to be painted or drawn. In particular, the system enables art students of all ages to select (a) the precise format to fit on the canvas to be drawn or painted, (b) the precise portion of the image desired to be painted or drawn, and (c) the precise overall composition of the final painting or drawing. 
     A significant feature of the preferred embodiment of the invention provides a series of graduated grid patterns with the artist selecting the grid pattern corresponding to the size of the canvas to be painted or drawn. For increased gridding detail, the invention provides overlay patterns having a reduced grid size. 
     Certain of the preferred embodiments of the invention include a series of image-guides, including large image-guides and detail image-guides, a corner-guide, a set of canvas tables, a ruler with a set of scales for marking canvas grids, and in some embodiments, pre-gridded canvases or back-shadowing transparencies for placing behind canvases and illuminating from the back. 
     Other preferred embodiments of the invention include computer generated graduated image-guides combined with a source image and displayed or printed for artists to use for creating a likeness of the image onto a destination base or canvas. 
     The series of graduated image-guides are preferably rectangular arrays of rectangular grid cells that are typically identical squares and advantageously pre-printed on clear plastic film or other clear material. The grid patterns consist of, for example, 8 rows by 10 columns forming 80 cells. A bold rectangle outlining the grid array will be called a composition frame and actually represents what could be a frame around the final drawing or painting, but sized at the source image scale. That is, the composition frame of the image-guide substantially represents the frame of the canvas reflected onto the source image. This composition frame allows the artist to easily visualize the final composition on the image that will be drawn onto the canvas without concentrating on the canvas, image grid lines, canvas grid lines, magnifications, and the like. To facilitate this understanding, the image-guide composition frame may appear as a picture frame with representations of wooden molding strips mitered at the comers and/or matte materials or the like. 
     A significant feature of this invention is that the image to be painted or drawn is configured with a grid pattern identical to the grid pattern drawn or otherwise applied to the canvas, i.e., the invention provides identical grid patterns and number of cells for both the canvas and the image and thereby greatly facilitates the gridding process. Thus, for example, for a predetermined grid array such as 8 rows by 10 columns—there is no requirement for the user to calculate magnification ratios, analyze candidate grid sizes, and the like. Eight by ten cells in an image-guide relates to eight by ten cells on any size 0.80 aspect ratio canvas, so that each has the same number, eighty cells total. The larger the canvas, the larger the canvas grid dimensions, always resulting in eighty canvas cells. Likewise, the larger or smaller an image, the larger or smaller are its grids and composition frame of the 80 cells of the image-guide. In this way, the eight by ten pattern can be used for any canvas of that aspect ratio, and by choosing an image-guide with its frame of the appropriate size; substantially any practical image size of that aspect ratio may be utilized as well. 
     For most common canvas sizes it has been found that the dimensions are divisible by a series of only a few canvas grid ruler scales. Substantially all may be generated with multiples of ½ inch, ⅝ inch, ¾ inch, and ⅞ inch so that a simple-to-use canvas ruler can be constructed. 
     The 0.80 aspect ratio image-guides are useable with other canvas shapes. A corner-guide consisting of two intersecting heavy lines or depictions of picture frame molding, for example, may be used for masking while continuing to create what represents a frame, used for framing the source image when the aspect ratio is not 0.80. The corner-guide is placed at the intersection of the row and column, or fractions thereof, appropriate for a specified canvas aspect ratio. 
     The series of image-guides of grid size 0.20 through 1.00 inch may include, for example, eight overlay sheets increasing in 26% linear dimension steps. In this way, an artist may compose an image with flexibility for increasing or decreasing its size in 26% steps in order to frame a desired region. For more flexibility, fifteen uniform 12% steps may be provided, or twenty-nine uniform 6% steps, for example. 
     Since all 0.80 aspect ratio canvas sizes require 8 rows and 10 columns, each such canvas size requires a unique grid pattern. Thus a 16 by 20 inch canvas will require a 2.00 inch grid spacing, and can be manufactured with that pattern and with labels, a further advantage and facet of the present invention. Likewise, for use with the above-described image-guides, a 24 by 30 inch canvas will uniquely require 3.00 inch grid spacing and may be pre-printed. Additionally, other aspect ratio canvas shapes will require unique grid patterns when used with the 8 by 10 shape image-guides. For example a 15 by 20 inch canvas requires 2.0 inch grid spacing and can be pre-printed with 7 ½ rows by 10 columns for its 0.75 aspect ratio. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In order to more fully understand the manner in which the above-recited and other advantages of the invention are obtained a more particular description of the invention will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. Understanding that these drawings depict embodiments of preferred embodiments of the invention and are therefore not to be considered limiting of its scope, the invention in its presently understood best modes for making and using the same will be described with additional specificity and detail through the use of the accompanying drawings in which: 
     FIG. 1 depicts an acetate sheet with two series  80  image-guides of the present invention. 
     FIG. 2 depicts another acetate sheet with two additional series  80  image-guides of the present invention. 
     FIG. 3 illustrates the use of a size  9  image-guide of the invention. 
     FIG. 4 illustrates the use of a size  7  image-guide of the invention. 
     FIG. 5 illustrates the use of a size  9  image-guide in the drawing of a likeness of an image onto two canvas sizes. 
     FIG. 6 depicts several frames of image-guides superimposed over an image to illustrate the magnification adjustment of the invention. 
     FIG. 7 depicts the use of a size  11  image-guide with a size  5  detail image-guide for creating a likeness of fine detail within the image. 
     FIG. 8 illustrates a region of a canvas in which detail from the image of FIG. 7 is drawn, showing canvas grid lines and canvas detail grid lines. 
     FIG. 9 illustrates a corner-guide for adjusting the frames of image-guides wherein the frames represent wooden picture frames. 
     FIG. 10 illustrates a corner-guide used with an image and image-guide, with a wooden picture frame representation, for a canvas of 0.50 aspect ratio. 
     FIG. 11 illustrates one embodiment of the first side of a ruler for making grid lines on the canvas showing scales  1  and  3 . 
     FIG. 12 illustrates the second side of the ruler of FIG. 11 showing scales  2  and  4 . 
     FIG. 13 depicts a back-illuminated canvas grid. 
     FIG. 14 illustrates the use of a back-illuminated canvas grid. 
     FIG. 15 depicts an acetate sheet with two series  20  image-guides of the present invention. 
     FIG. 16 depicts the use of a software-generated image-guide for drawing a likeness onto a canvas. 
     FIG. 17 depicts a software program for generating and displaying images with image-guides of FIG.  16 . 
     FIG. 18 illustrates both sides of an alternate canvas ruler showing scales A, B, C, and D. 
     FIG. 19 illustrates a preferred embodiment of the Canvas Table for determining canvas ruler scale and markings, and grid sizes for any canvas size. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     For purposes of this patent, the term “canvas” shall include the destination base for drawings and paintings, typically made of canvas over a wooden rectangular structure. Destination bases such as paper, felt, fabrics, T-shirts, and the like shall also be included in this meaning. Canvas may also refer to a stucco wall, interior wall, and any other material or structure onto which an artist or drawer applies his or her work. The term “likeness” denotes the artist&#39;s work as derived from an original, including a copy, duplication, or replication, and in the context of this patent, likeness and replication shall both include drawings made at different magnifications or sizes than the original. 
     FIG. 1 depicts a preferred embodiment of an image-guide. Sheet  200  is advantageously clear plastic on which are printed one or more image-guides from a series. In the embodiment shown, image-guide  11   212  and image-guide  1   218  are printed on the same sheet and later separated by the user by cutting along cut-path  216 . Each image-guide contains 8 rows and 10 columns. Image-guides are identified with a sheet number from a series, such as sheet number  11  in image-guide- 11   212  which includes vertical grid lines  204  and column labels  206  along with horizontal grid lines  208  and row labels  210 . Image-guide- 11  composition frame  202  boldly outlines the eighty square cells formed, including cell E 7   214  at the intersection of the 7th column and row “E”. Image-guide- 11   212  cell E 7   214  may be 0.630 inch along each side whereas image-guide-l  218  cell E 7   215 , may be 0.198 inch along each side. 
     It has been found that 80 cells is a convenient density of cells for many artists. However, other patterns, such as 12 rows by 15 columns can be provided for artists favoring higher densities, and lower densities such as 4 rows by 5 columns can be provided for artists favoring lower density grid patterns and for some children. Additionally, other aspect ratios could be used in place of the 0.80 aspect ratio all within the scope of the present invention. 
     Thus with only a few image-guides, such as approximately eight to twenty-nine, substantially all practical images and all canvases of a particular aspect ratio, such as height/width=0.80 can be accommodated. 
     The set of 8 row by 10 column image-guides may be termed series  80 , and may include image grid sizes from 0.20 inch squares to 1.00 inch squares, for example, resulting in image-guide composition frames ranging from 1.6 inches by 2.0 inches to 8.0 inches by 10.0 inches. 
     Sheet  200  is advantageously forward from a polycarbonate or an acetate preferably 8 ½ inches by 11 inches and approximately 0.004 inch thick as is commonly used for producing transparencies using laser copiers and printers, and is readily available at low cost due to high volume production. Such sheets are available from Apollo Co., 60 Trade Zone Court, Ronkonkoma, N.Y. 11779 and provided in package PP 100C. 
     To manufacture image guides, the lines and features may be imprinted using a laser printer. To discourage illegal copying of image-guides onto acetate sheets, substantially non-copyable image-guides may be produced using white ink or paint in a silkscreen process, or white toner material made with titanium dioxide, for example, and available from KLE, P.O. Box 2452, Jupiter, Fla. 33468; Tel: (561)743-0636 and also reachable on the internet at ColorToner.com on the internet. Laser printing may be accomplished using a Lexmark printer model number 4039 10 Plus, available through KLE noted above. Printing may be provided on either the front or the back surface to optimize durability in view of the use of tape, described below, which may tend to lift the printing if used carelessly. 
     FIG. 2 depicts a companion image-guide sheet  220  with image-guide- 9   224  and image-guide- 5   226  separable by cutting along cut-path  216 . Image-guide- 9   224  composition frame  222  outlines the eighty cells of the 8 rows by 10 columns. 
     The image-guides of FIG.  1  and FIG. 2 are advantageously members of a set of image-guides with grids and composition frames increasing in size from one image-guide to the next. In one preferred embodiment, the set includes 18 image guides with a step of 12.25% from one image-guide to the next in the set and shown tabulated in TABLE I below. 
     As described below, it is desirable to provide detail image-guides for each of the large image-guides so that large cells may be divided into four, for example, detail cells using one of the smaller image-guides in the series. It is also desirable to include 0.250 inch, 0.500 inch, and 1.00 inch in the series and for the series to 
     
       
         
               
             
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                 TABLE I 
               
             
             
               
                   
               
               
                 Eighty-cell Image-guide Grid and Composition frame dimensions. 
               
             
          
           
               
                   
                   
                 Composition 
                 Composition 
                   
               
               
                 Image 
                 Cell 
                 Frame 
                 Frame 
                 Useable also as a 
               
               
                 Guide 
                 Side, 
                 Height 
                 Width 
                 detail image-guide 
               
               
                 Sheet No. 
                 Inch 
                 inches 
                 inches 
                 for Sheet No.: 
               
               
                   
               
             
          
           
               
                 1 
                 0.198 
                 1.59 
                 1.98 
                 7 
                 (13)* 
               
               
                 2 
                 0.223 
                 1.78 
                 2.23 
                 8 
                 (14)* 
               
               
                 3 
                 0.250 
                 2.00 
                 2.50 
                 9 
                 (15)* 
               
               
                 4 
                 0.281 
                 2.24 
                 2.81 
                 10 
               
               
                 5 
                 0.315 
                 2.52 
                 3.15 
                 11 
               
               
                 6 
                 0.354 
                 2.83 
                 3.54 
                 12 
               
               
                 7 
                 0.397 
                 3.17 
                 3.97 
                 13 
               
               
                 8 
                 0.445 
                 3.56 
                 4.45 
                 14 
               
               
                 9 
                 0.500 
                 4.00 
                 5.00 
                 15 
               
               
                 10 
                 0.561 
                 4.49 
                 5.61 
               
               
                 11 
                 0.630 
                 5.04 
                 6.30 
               
               
                 12 
                 0.707 
                 5.66 
                 7.07 
               
               
                 13 
                 0.794 
                 6.35 
                 7.94 
               
               
                 14 
                 0.891 
                 7.13 
                 8.91 
               
               
                 15 
                 1.000 
                 8.00 
                 10.00 
               
               
                   
               
               
                 *Detail image-guides shown for 2:1 and those indicated ( )* for 4:1  
               
             
          
         
       
     
     span a grid range of approximately 0.20 inch to 1.0 inch as found by practical experience of artists and students. Defining: 
     p=increase in edge dimension per image-guide step, percent; 
     n=number of image-guide sizes from any detail image-guide and its corresponding large image-guide 
     d=number of linear subdivisions a detail image-guide divides its corresponding large image-guide into; 
     then the size step, p, is found from: 
     
       
           p =100( n   d −1) %  [1] 
       
     
     For example, for d=2 and only one step from a 0.250 grid size to a 0.500 grid size, solving equation [1]for n=1 leads to p=100%. This indicates that if the 0.25 inch grid dimension is increased by 100% to 0.50 inch, there would be no intermediate image-guides between the 0.25 and 0.50 inch image-guides if n=1. 
     For n=3, p=26%, and for n=6, p=12.25%, with 2 intermediate and 5 intermediate image-guides respectively between and including 0.25 and 0.50 inch grid spacings, and 8 and 15 image-guides respectively between and including 0.2 and 1.0 inch grid spacings. For n=12, p=5.95%, 29 image-guides between and including 0.2 and 1.0 inch grid spacings result, providing an artist with great flexibility in magnification when composing a composition over an image with the choice of 29 composition frame sizes. Other values of d may be provided for detail guides, such as 3, in which case each image-guide cell or square would be divided into 3 horizontally by 3 vertically for nine detail cells or sub-squares. The preferred embodiment utilizes d=2 for subdividing each image-guide cell into four detail cells, and for certain cases shown in Table I with ( )*, a subdivision of 4 by 4 results. 
     Table I provides the grid side cell dimension, composition frame height, and composition frame width of all 15 image-guides in the series  80  set with n=6. Odd numbered image-guides of Table I represent the 8 image-guides spanning the range of 0.20 inch to 1.0 inch with n=3, and for the set of n=12 there may be an intermediate image-guide, not shown, between each of those shown in the table. It has been found that the n=3 set with 26% size increments between image-guides is useful for beginning artists, and that for increased ability to compose an image, n=6 with 12% size increments between image-guides is useful, in which case all 15 sheets of Table I would be provided. Professional artists interested in fine magnification steps for exceptional flexibility may choose a set of 29 image-guides, or a larger set, for example. 
     The image size range, which is the range in size of the composition frames, of the image-guides in Table I covers 1.6 by 2.0 inches to 8.0 by 10.0 inches. This range could be extended if desired by providing smaller and/or larger image-guides in the series. 
     FIG. 3 illustrates the use of a detail image-guide to grid only a portion of a picture  100  and thus magnify a selected portion of the picture  200  to be painted or drawn on the canvas  230 . Image-guide- 9   224  is placed on picture  100  to enclose an image area with composition frame  222 , which is replicated onto the canvas  230  which has been gridded in the manner described below with vertical grid lines  231  and column labels  232 , and with horizontal grid lines  233  and row labels  234 . 
     FIGS. 3 and 4 taken together illustrate the adjustment in composition area achieved by using a smaller image-guide- 7   226  in FIG. 4 in place of image-guide- 9   224  of FIG.  3 . In these two figures picture  100  size is the same, such as 8 by 10 inches, and canvas  230  size is the same, such as 16 by 20 inches. The area covered by image-guide- 9   224  is enclosed by composition frame  222 , and a smaller area covered by image-guide- 7   226  is enclosed by composition frame  225 . Since image-guide- 7   226  covers a smaller image area on picture  100  than does image-guide- 9   224 , and the image area in each case is magnified to cover the full canvas  230 , the magnification of image-guide- 7   226  is greater than that of image-guide- 9   224 , and the composition  239  in FIG. 4 is of a smaller region of the scene than the composition  238  in FIG.  3 . It is thus seen that small adjustments in composition can be accomplished through selection of image-guides used, and the actual composition can be viewed within the image-guide composition frame upon the image without paying attention to the canvas. The side dimension of grid  236  may be calculated from the canvas  230  width by the number of columns, 10. Therefore canvas grid  236  measures 20 inches/10 =2.0 inches on a side. However, it is not necessary for an artist to calculate or know the canvas grid size since the canvas gridding scale is provided in a table, as described below. Image magnification may be determined by canvas grid size/image grid size. From Table I image-guide- 9  grid size is 0.50 inch, so the magnification is 2.0 inches/0.50 inch=4.0. However, an artist is not required to calculate or know the value of magnification. The magnification of image-guide- 7   226  to canvas  230  in FIG. 4 is 2.0 inches/0.397 =5.0. 
     After choosing the general composition area by selecting an image-guide, an artist translates the image-guide horizontally and vertically over picture  100  to adjust the composition that will appear on the canvas. The composition frame of the image-guide serves as a representation of the canvas edges over the picture, which allows the artist to better optimize the composition and do it very quickly. Once the composition is defined, the artist may secure the image-guide to the picture using tape  228 , such as masking tape commonly used in drafting. 
     The foregoing discussion has related to compositions in the landscape orientation in which the horizontal dimension is larger than the vertical dimension. The portrait orientation involves images in which the vertical dimension is larger than the horizontal dimension. All that is required to replicate an image in the portrait orientation is a 90-degree counter-clockwise rotation of the image-guide, and a corresponding positioning of the canvas. In this way, cell A- 1  is located in the lower left comer rather than the upper left comer. The remainder of this description will describe images and compositions in the landscape orientation, it being clear that these features and improvements apply equally to images and compositions in the portrait orientation. 
     FIG. 5 compares the use of image-guide- 9   224  secured to image  100  with tape  228  and used for two canvas sizes to illustrate that the image composition is independent of canvas size when using the system of the present invention. In this way the artist can focus concentration with respect to her composition strictly on the picture and the image-guide composition frame. The upper canvas  230  is similar to that of FIG.  3  and may be 16 by 20 inches, whereas the lower canvas  240  may be 24 by 30 inches, for example. It was previously found that cell  236  measured 2.0 inches on a side and that the magnification ratio was 4.0 from image-guide- 9   224 . For the lower canvas  240 , the grid dimension is found from the canvas width/ 10 , and is 3.0 inches. The magnification from the image to the lower canvas  240  is therefore 3.0/0.50=6.0. Using the system of this invention, an artist will, however, not be concerned with magnification ratios or with grid dimensions of either image or canvas. She simply chooses the canvas, frames the image with the image-guide to her liking, tapes the image-guide in place on the picture, and proceeds to grid the canvas according to a color-coded ruler to be described. 
     It is evident from these figures and discussion that for Series  80 , the canvas grid size is not related to the image-size or the specific image-guide in use, but is related only to the canvas dimensions. Therefore canvases of this invention may be pre-printed with grids and labels and will be useable with all image-guides of Table I, and any picture within the image size range of the image-guides will then be useable with any canvas. Therefore canvas  230  may be imprinted using a silk-screening process for placing grid lines and labels thereon, a process well known in the art. Silk-screening is a stencil method of printing on a flat surface through a piece of silk or other fine cloth on which all parts of the design not to be printed have been stopped out by an impermeable substance. FIG. 6 further illustrates the simplified adjustment in composition image area within picture  100  wherein five composition frames are depicted from five image-guides of Table I. Frame  305  represents the outline of the grid pattern of image-guide  5 . The remaining frames  306 ,  307 ,  308 , and  309  represent the composition frames of image-guides  6 ,  7 ,  8 , and  9  respectively. 
     A significant feature of the invention is that the larger image guide sheets are readily combined with another mark detailed image guide sheet whenever the artist desires to use additional grid lines for a portion of the photograph  100  or other original being used by the artist to create a likeness on a canvas. FIG. 7 depicts picture  100  overlaid with image-guide  11   212  secured with tape  228 , and further overlaid with a second image-guide  5   226  secured with tape  328  over a region for which the artist desires a smaller grid spacing for fine detail. 
     When a more detailed image grid is overlaid an image-guide as shown in FIG. 7, the artist will advantageously also grid a portion of the canvas with a smaller grid spacing corresponding to the more detailed image guide. Depicted in FIG. 8 is a portion of a canvas  230  with vertical canvas grid lines  231  and horizontal canvas grid lines  233 , previously discussed, upon which detail vertical canvas grid lines  331  and detail horizontal canvas grid lines  333  are constructed. Detail row and column canvas labels  334  and  332  respectively may be drawn onto the canvas. Other preferred embodiments, not shown, employ detail row labels J through Q and detail column labels  11  through  20  for clarifying cell identifications, on both detail image-guides and on canvas detail regions. 
     It will further be seen that substantially all canvases are useable with the image-guides of Table I, even if their aspect ratios are not 0.80. For canvas shapes other than 0.80 aspect ratio, the set of 8 row by 10 column image-guides are useable by simply masking or ignoring certain rows, columns, or fractions thereof, or by extending slightly beyond the 8 rows by 10 columns to frame the desired image area for composing the drawing shape to match the canvas shape. For example, 0.50 aspect ratio canvases may be framed with the 4 row by 8 column sub-array of the 8 row by 10 column image-guides, or with the 5 row by 10 column sub-array. Additionally, square canvases may be framed using the 8 row by 8 column sub-array or the 7 row by 7 column sub-array, for example, of the 8 row by 10 column image-guides. As further example, a canvas with an aspect ratio of 0.75, such as a 15 inch by 20 inch canvas, may be accommodated with the 8 row by 10 column image-guides by utilizing a sub-array of 7 rows by 10 columns and additionally including one-half of a row, so that the masked image-guide involves 7.5 rows by 10 columns generating a composition frame of aspect ratio of 0.75, matching the aspect ratio of the desired canvas for the composition. Thus the composition frame modified by the masking of the image-guide will frame a shape on the image substantially identical to the shape of the canvas. 
     FIG. 9 illustrates a comer-guide  300  constructed, according to the method for constructing image-guides, on clear acetate sheet material  302  for aligning with row and column positions on images that have aspect ratios other than 0.80. A row alignment line  303  and a column alignment line  304  intersect at a 90-degree corner to be oriented over an image-guide and positioned at predetermined row and column locations to generate a modified image-guide of differing aspect ratio. A section of a picture frame  306  with mitered corner  308  helps in visualization of the final composition. FIG. 10 illustrates the use of a 0.50 aspect ratio image region for a 0.50 aspect ratio canvas such as a 12 by 24 inch canvas. TABLE II-c to be described below is used to identify the row and column alignments for comer-guide  300  for 0.50 aspect ratio canvas shapes. The comer-guide is secured to Image-guide  11   312  with tape  229 , and the image composition is adjusted horizontally and vertically over picture  100 . This preferred embodiment of the image-guide also includes a representation of a picture frame  310  to aid in composing the image. After the composition is defined, the combined image-guide with comer-guide is secured to picture  100  with tape  228 . 
     Canvas tables may be provided to reference all common canvas sizes and may group all canvases according to aspect ratio. The canvas tables additionally provide a reference to the appropriate scale on a canvas ruler which can be used to simplify marking of the canvas for location of grid lines, typically accomplished with some difficulty using a normal ruler. The scales on the canvas ruler are simplified in order to present only the information pertinent to the specific class of grid dimensions. For example, scale  1  might include black indicators at every ½-inch location, black arrows at every 1.0 inch location, red markers with black arrows at every 2.0 inch location, and blue markers with red markers and with black arrows at every 4.0 inch location. Such a scale is very easy to use for locating each grid line for ½-inch, 1.0 inch, 2.0 inch, and 4.0 inch canvas grid spacings. A larger canvas ruler may include, for example, green markers at every other blue marker and yellow markers at every other green marker forming easy to use guides for 8.0 and 16.0 inch canvas grids as well, for painting wall murals, for example. Yet larger grids may be constructed using 1.0, 2.0, 4.0, and 8.0 feet, for example, for painting large compositions such as highway billboards. 
     Another significant feature of the invention is to greatly simplify the proper spacing for grid lines being drawn on the canvas. Such grid lines are drawn upon a canvas that has not been pre-gridded and also upon pre-gridded canvases when the artist desires to use a more detailed image-guide as discussed above with reference to FIGS. 7 and 8. 
     FIG. 11 illustrates a ruler  340  for gridding a canvas. The first side  342  of ruler  340  advantageously includes an instruction statement  341 , a scale  1   344  and a scale  3   346 . Scale  1   344  includes three types of secondary scale divisions, all power-of-2 multiples of a ½ inch primary division, that is, 1.0 inch, 2.0 inches, and 4.0 inches. Arrow-markers  350  are located 1.0-inch apart for easily marking a canvas for 1-inch canvas grids, and simple line markers  348  are useful for subdividing the 1-inch arrow-markers  350  in half for generating detail grid lines spaced at ½ inch. Single-box markers  352 , which may be colored red, for example, are located at 2.0-inch spacings for easily marking a canvas for 2-inch canvas grid lines. Double-box markers  354 , which may be colored blue, for example, are located at 4.0-inch spacings for easily marking a canvas for 4-inch canvas grid lines. Scale  1   344  may be used on the top of the face of a canvas, not shown, to mark the canvas for grid lines, for which a pencil may be used, for example. An inverted scale label  345  allows a user to flip the canvas-ruler end-for-end and align along the bottom of the canvas face to mark the canvas for grid lines so that the opposing top marks and the bottom marks may be connected with lines to form canvas grid lines parallel to the left edge of the canvas structure. In like manner horizontal canvas grid lines may be constructed normal to the vertical lines using the same canvas-ruler markers, forming squares. 
     The type of marker used to make the grid lines will depend, in part, on the painting media used by the artist. Generally, oil paints completely cover the grid lines so that erasure or removal is not necessary. For water colors, however, the grid lines are preferably drawn on the canvas with an easily erased media such as a #2 pencil. A gum eraser is effective for erasing the grid lines after the artist has completed the outline on canvas  200 . 
     Scale  3   346  includes three types of secondary scale divisions, all multiples of a ¾ inch primary division. Simple line markers  360 , arrow-markers  362 , small-box markers  364 , and large-box markers  366  are provided for ¾ inch, 1.5-inch, 3-inch, and 6-inch canvas grid patterns respectively. Any of these scales may be used for generating detail grid patterns for the next-larger grid spacing. 
     Canvas-ruler 340 may preferably be approximately 1-½ inches wide and 11-½ inches in length and constructed of, for example, heavy paper or cardboard using printing methods well known in the art, and allows use with most common canvas sizes, and may be used in a step and repeat fashion for larger canvas sizes. For larger canvases, a larger canvas ruler of the order of 26 inches long may be utilized. For increased durability the canvas-ruler may be sealed within a clear plastic structure, or laminated, a process well known in the printing business. 
     FIG. 12 shows the second side  370  of ruler  340  that includes a scale  2   372  and a scale  4   374 . Scale  2   372  includes three types of secondary scale divisions, all multiples of a ⅝ inch primary division. Scale  4   374  includes three types of secondary scale divisions, all multiples of a ⅞ inch primary division. Both scales include simple line markers, arrow markers, small-box markers, and large-box markers, useable in similar fashion to those of FIG.  11 ( a ). 
     FIG. 18 illustrates a preferred embodiment of a canvas ruler  398  approximately 1-½ inches wide and 11-½ inches long, showing first side  380  with scale A  382  and scale B  384 , and second side  392  with scale C  394  and scale D  396 . Canvas ruler  398  includes instruction statements (“EDGE”), scale divisions, line markers and arrow symbols that function similar to those of FIG.  11  and FIG. 12 described above. Each scale of canvas ruler  398  includes primary scale markers  386  without arrow heads, and secondary scale markers  388  and also includes marker grid dimensions  390  that identify the grid space dimensions for corresponding canvas grid lines, in inches. Secondary scale markers  388  may include sole arrow tip markers  363  analogous to arrow-markers  362  of FIG. 11, single trapezoidal box markers  365  with arrow tips analogous to the single box markers  364  of FIG.  11  and double trapezoidal box markers  367  with single trapezoidal boxes and with arrow tips analogous to the double box markers  366  of FIG.  11 . The single trapezoidal box markers  365  shown white may be advantageously colored red, for example, for clarity, and the larger trapezoidal box of the double trapezoidal box markers  367  shown crosshatch in FIG. 18, may be advantageously colored blue for clarity. 
     TABLE II illustrates another format of canvas tables provided for users to locate their canvas size and determine the appropriate canvas ruler scale and marker. Also included are grid sizes, and for non 8 by 10 canvas shapes, the enclosed rows or fractions thereof and enclosed columns or fractions thereof for use with corner-guides previously described. Users align and tape the corner-guide over an image-guide according to the table entries for their canvas. 
     
       
         
               
             
               
               
               
               
               
             
               
               
               
               
               
             
               
             
               
               
               
               
               
               
             
               
               
               
               
               
               
             
               
             
               
               
               
               
               
               
             
               
             
               
               
               
               
               
               
             
           
               
                 TABLE II 
               
               
                   
               
               
                 Canvas Tables 
               
               
                   
               
             
             
               
                 a. Canvas Shapes with 0.80 Aspect Ratio 
               
             
          
           
               
                 Canvas 
                 Ruler 
                 Ruler 
                 Canvas 
                 Canvas 
               
               
                 Size 
                 Scale 
                 Marker 
                 Grid, in. 
                 Grid, cm. 
               
               
                   
               
             
          
           
               
                  8 × 10 
                 1 
                 All arrows 
                 1.0 
                 2.54 
               
               
                   10 × 12.5 
                 2 
                 All arrows 
                 1.25 
                 3.18 
               
               
                 12 × 15 
                 3 
                 All arrows 
                 1.5 
                 3.81 
               
               
                   14 × 17.5 
                 4 
                 All arrows 
                 1.75 
                 4.45 
               
               
                 16 × 20 
                 1 
                 All small 
                 2.0 
                 5.08 
               
               
                   
                   
                 boxes 
               
               
                 20 × 25 
                 2 
                 All small 
                 2.5 
                 6.35 
               
               
                   
                   
                 boxes 
               
               
                 24 × 30 
                 3 
                 All small 
                 3.0 
                 7.62 
               
               
                   
                   
                 boxes 
               
               
                 28 × 35 
                 4 
                 All small 
                 3.5 
                 8.89 
               
               
                   
                   
                 boxes 
               
               
                 32 × 40 
                 1 
                 All large 
                 4.0 
                 10.16 
               
               
                   
                   
                 boxes 
               
               
                 40 × 50 
                 2 
                 All large 
                 5.0 
                 12.70 
               
               
                   
                   
                 boxes 
               
               
                 48 × 60 
                 3 
                 All large 
                 6.0 
                 15.24 
               
               
                   
                   
                 boxes 
               
               
                 56 × 70 
                 4 
                 All large 
                 7.0 
                 17.78 
               
               
                   
                   
                 boxes 
               
               
                   
               
               
                 Note: All sizes may not be commonly available.  
               
             
          
           
               
                 b. Canvas Shapes with 1.0 Aspect Ratio (square) 
               
             
          
           
               
                   
                   
                   
                   
                 Corner- 
                 Corner- 
               
               
                   
                   
                   
                 Can- 
                 guide Last 
                 guide Last 
               
               
                   
                   
                   
                 vas 
                 or 
                 or 
               
               
                 Canvas 
                 Ruler 
                 Ruler 
                 Grid, 
                 Fractional* 
                 Fractional* 
               
               
                 Size 
                 Scale 
                 Marker 
                 in. 
                 Row 
                 Column 
               
               
                   
               
             
          
           
               
                 8 × 8 
                 1 
                 All arrows 
                 1.0 
                 H 
                 8 
               
               
                 10 × 10 
                 2 
                 All arrows 
                 1.25 
                 H 
                 8 
               
               
                 12 × 12 
                 3 
                 All arrows 
                 1.5 
                 H 
                 8 
               
               
                 14 × 14 
                 4 
                 All arrows 
                 1.75 
                 H 
                 8 
               
               
                 15 × 15 
                 1 
                 All small 
                 2.0 
                 ½ into H 
                 ½ into 8 
               
               
                   
                   
                 boxes 
               
               
                 16 × 16 
                 1 
                 All small 
                 2.0 
                 H 
                 8 
               
               
                   
                   
                 boxes 
               
               
                 20 × 20 
                 2 
                 All small 
                 2.5 
                 H 
                 8 
               
               
                   
                   
                 boxes 
               
               
                 24 × 24 
                 3 
                 All small 
                 3.0 
                 H 
                 8 
               
               
                   
                   
                 boxes 
               
               
                 28 × 28 
                 4 
                 All small 
                 3.5 
                 H 
                 8 
               
               
                   
                   
                 boxes 
               
               
                 30 × 30 
                 1 
                 All large 
                 4.0 
                 ½ into H 
                 ½ into 8 
               
               
                   
                   
                 boxes 
               
               
                 40 × 40 
                 2 
                 All large 
                 5.0 
                 H 
                 8 
               
               
                   
                   
                 boxes 
               
               
                 48 × 48 
                 3 
                 All large 
                 6.0 
                 H 
                 8 
               
               
                   
                   
                 boxes 
               
               
                 56 × 56 
                 4 
                 All large 
                 7.0 
                 H 
                 8 
               
               
                   
                   
                 boxes 
               
             
          
           
               
                 c. Canvas Shapes with 0.5 Aspect Ratio (2:1) 
               
             
          
           
               
                  6 × 12 
                 2 
                 All arrows 
                 1.25 
                 {fraction (8/10)} into E 
                 {fraction (6/10)} into 10 
               
               
                  8 × 16 
                 1 
                 All small boxes 
                 2.0 
                 D 
                 8 
               
               
                 10 × 20 
                 1 
                 All small boxes 
                 2.0 
                 E 
                 10  
               
               
                 12 × 24 
                 3 
                 All small boxes 
                 3.0 
                 D 
                 8 
               
               
                 15 × 30 
                 3 
                 All small boxes 
                 3.0 
                 E 
                 10  
               
               
                 16 × 32 
                 1 
                 All large boxes 
                 4.0 
                 D 
                 8 
               
               
                 20 × 40 
                 1 
                 All large boxes 
                 4.0 
                 E 
                 10  
               
               
                 24 × 48 
                 3 
                 All large boxes 
                 6.0 
                 D 
                 8 
               
               
                 28 × 56 
                 4 
                 All large boxes 
                 7.0 
                 D 
                 8 
               
               
                 30 × 60 
                 3 
                 All large boxes 
                 6.0 
                 E 
                 10  
               
             
          
           
               
                 d. Canvas Shapes with Other Aspect Ratio (not H-10) 
               
             
          
           
               
                  9 × 12 
                 2 
                 All arrows 
                 1.25 
                 {fraction (2/10)} into H 
                 {fraction (6/10)} into 10 
               
               
                 10 × 12 
                 2 
                 All arrows 
                 1.25 
                 H 
                 {fraction (6/10)} into 10 
               
               
                 10 × 14 
                 3 
                 All arrows 
                 1.5 
                 ⅔ into G 
                 ⅓ into 10 
               
               
                 10 × 15 
                 3 
                 All arrows 
                 1.5 
                 ⅔ into G 
                 10 
               
               
                 11 × 14 
                 3 
                 All arrows 
                 1.5 
                 ⅓ into H 
                 ⅓ into 10 
               
               
                 12 × 16 
                 4 
                 All arrows 
                 1.75 
                 {fraction (9/10)} into G 
                 ⅛ into 10 
               
               
                 14 × 18 
                 1 
                 All small boxes 
                 2.0 
                 G 
                 9 
               
               
                 15 × 18 
                 1 
                 All small boxes 
                 2.0 
                 ½ into H 
                 9 
               
               
                 17 × 24 
                 2 
                 All small boxes 
                 2.5 
                 ¼ into H 
                 ⅝ into 10 
               
               
                 20 × 24 
                 2 
                 All small boxes 
                 2.5 
                 H 
                 ⅝ into 10 
               
               
                 22 × 28 
                 3 
                 All small boxes 
                 3.0 
                 ⅓ into H 
                 ⅓ into 10 
               
               
                 20 × 30 
                 3 
                 All small boxes 
                 3.0 
                 ⅔ into G 
                 10  
               
               
                 22 × 30 
                 3 
                 All small boxes 
                 3.0 
                 ⅓ into H 
                 10  
               
               
                 24 × 36 
                 4 
                 All small boxes 
                 3.5 
                 ⅞ into G 
                 ⅓ beyond 
               
               
                   
                   
                   
                   
                   
                 10 
               
               
                 30 × 40 
                 1 
                 All large boxes 
                 4.0 
                 ½ into H 
                 10  
               
               
                 36 × 48 
                 2 
                 All large boxes 
                 5.0 
                 ¼ into H 
                 ⅝ into 10 
               
               
                 48 × 56 
                 3 
                 All large boxes 
                 6.0 
                 H 
                 ⅓ into 10 
               
               
                 60 × 72 
                 4 
                 All large boxes 
                 7.0 
                 ½ beyond 
                 ¼ beyond 
               
               
                   
                   
                   
                   
                 H 
                 10 
               
               
                 60 × 72 
                  1** 
                 Alternate 
                 8.0 
                 ½ into H 
                 9 
               
               
                   
                   
                 large boxes 
               
               
                   
               
               
                 *Fractional values rounded to convenient fractions of rows and columns  
               
               
                 **Alternative to entry above  
               
             
          
         
       
     
     An alternative method to Table II for determining an appropriate canvas grid spacing is the following algorithm in which Canvas Grid may be in inches or centimeters according to the measurement units used below: 
     1. Measure the long dimension of the canvas to be used and divide it by 10 to obtain ‘calculated canvas grid’. 
     2. Using ‘calculated canvas grid’ for ‘Canvas Grid’, enter table II-a to find the scale and marker. 
     3. If ‘calculated canvas grid’ is not found in the table, ‘Canvas Grid’ becomes the next larger grid size found in the table. 
     4. If 8.00 X ‘Canvas Grid’&lt;canvas short dimension, use the yet next larger grid size in the table for Canvas Grid to find the scale and marker. 
     Users apply grids and labels to a canvas, and then tape a comer-guide to their image-guide in preparation for drawing. 
     FIG. 19 illustrates a preferred canvas table  600  which tabulates substantially all common canvas sizes in the English system, showing height and width measurements in inches, such as, for example, 12×15 canvas  602  that measures 12 inches high by 15 inches wide. 
     All canvases in COLUMN  1   604  have aspect ratios of 0.80 similar to those shown in Table II-a, and share the same aspect ratio of the preferred embodiment image-guides of Table I, therefore not requiring the use of a comer-guide previously described. Other canvas shapes are tabulated in the remaining columns  606  similar to Tables I-b, -c, and -d previously described. 
     Ruler Information  610  includes Ruler Scale column  612 , Marker Description column  614 , and Ruler Grid Markers column  616  which identify the specific ruler parameters for use for each canvas along the corresponding row to the left in canvas table  600 . Though it is not necessary for the artist to actually be concerned with or know the value of the grid dimension, it is shown on canvas table  600  in the Grid Size column  618  showing marker grid dimensions  390  as previously described for FIG.  18 . 
     Canvas ruler primary markers  386  without arrowheads, previously described in conjunction with FIG. 18, are indicated for use with small canvas sizes and therefore correspondingly small primary grid sizes  608 . Somewhat larger canvas sizes, for example 12×15 canvas  602 , utilize the indicated secondary grid markers  388  on the indicated Ruler Scale  620  as found in Ruler Information  610  along the row in which the canvas is located within canvas table  600 . Thus it is found that 12×15 canvas  602  uses canvas ruler scale C  620  and Marker Description  622  “USE EVERY ARROW THAT HAS BLACK”. Ruler Grid Markers  388  on ruler scale C are therefore used to grid 12×15 canvas  602  of the example, which is a 1-½ inch grid  624 . 
     It should be understood that for larger canvases, such as the commonly used 20 inch by 24 inch canvas  626 , not every scale marker is to be used, as shown in Ruler Grid Markers  628  in which the sole arrow tip markers  363  of FIG. 18 without single or double trapezoidal boxes is excluded from use for canvases in this size group. In similar fashion, yet larger canvases use only every arrow that has blue, or cross-hatching in FIG.  19 . 
     The generality that image-guides of Table I all contain 80 cells allows an artist to easily establish grid dimensions for general measurement units described in statement  630 . Furthermore, canvas or drawing surfaces of any size in any unit of measure may be gridded by using grid calculation method  632  of FIG.  19 . 
     FIG. 13 depicts a grid transparency  400  for gridding a canvas. Member  400  is constructed preferably of polycarbonate, acetate or other clear, flexible material approximately 0.010 inch thick with canvas grid lines  402 , row and column labels  404  attached thereto. The method of manufacture may be photographic or silk-screening, for example, onto standard plastic sheet, methods well known in the graphics field. The grid lines may be dark upon clear material, or clear lines within opaque background such that the transparency produces white or lighted lines and labels against dark. 
     Canvas grid transparency  400  is placed behind a canvas  410  illustrated in FIG.  14  and captured around the edges between the canvas material and the wooden canvas structure on the backside to temporarily attach transparency  400  to the rear of the canvas  410 . Canvas  410  is shown on easel  112  for clarity, and is back-illuminated through grid transparency  400  by illuminator  412  casting light rays  414  so that the grid lines  402  show up in the artist&#39;s side of the canvas. Illuminator  412  may be a light bulb or sunlight, for example. 
     FIG. 15 illustrates an acetate sheet  120  with two preferred embodiment series  20  image-guides  124  and  126  in which there are 4 rows and 5 columns that form 20 cells, and shown utilizing a simulated wooden picture frame  122  for the composition frame. Cut line  216  previously discussed separates the two image-guides. Row and column labels  110  identify the five columns and four rows of vertical and horizontal grid lines  108 . 
     Other preferred embodiments of the invention automatically grid the original image with computer-generated image grids. Thus, FIG. 16 depicts another preferred embodiment wherein software-generated image-guide  420  includes frame  422 , horizontal and vertical grid lines  424 , and row and column labels  426  displayed upon computer monitor  430 . A personal computer  432 , keyboard  434 , mouse  436 , and internal computer components  438  including operating system software  440  as well known in the art, are interconnected to display scenes  428  onto computer monitor  430 . Included within internal computer components  438  is specialized software  442  of this invention to be described below, along with other elements not illustrated but well known in the art, including random access memory, read only memory, logic, hard disks, a compact disk reader, CDs, a modem, a power supply and other elements not shown. A labeled and gridded canvas  230  as described for FIG. 3 is shown on easel  112  for clarity. In a fashion similar to that described for FIGS.  3  through FIG. 8, an artist creates a likeness upon canvas  230  from an image from scene  428  that is enclosed by frame  422 . The combination displayed upon computer monitor  430  may be printed from printer  444  and used in similar fashion to create a likeness of the image onto canvas  230  also within the scope of this invention. Scene  428  may be a scanned picture from scanner  446 , a scene from a compact disk or CD, a scene from a digital camera or video camera, or a scene from the internet obtained from internet connection  448 , for example. 
     With the aid of personal computer  432  and specialized software  442  substantially any magnification may be created, landscape or portrait orientations of the software-generated image-guide  420  may be generated. Modes of display may be provided wherein only the frame is displayed, which may also be a likeness of a picture-frame. Some regions outside of the composition frame may be dimmed or obscured to emphasize the composition region. 
     Canvas Tables in memory may be utilized in the specialized software  442  so that an artist may choose her canvas size, and frame  422  thereupon adjusts to include the appropriate rows and columns, and any required fractions thereof to serve the function of the corner-guide of FIG.  9  and FIG.  10 . Zoom capabilities may be included to allow a user to enlarge the active cell of the grid pattern on which she is working, and for detail image areas, and 2:1 grid resolutions may be displayed in fashion similar to detail grids previously described. Other detail grid resolutions may be displayed as well. Frame  422  is a software-generated rectangle that represents the destination canvas, and may be modified by selecting either canvas aspect ratio or specific canvas dimensions. The software program then provides canvas grid application instructions to the user, such as canvas-ruler scale and marker. Menu  429  provides a user with a selection of software program actions. A user may modify the composition frame by mouse-selecting frame modifier box  416  and drag to create a new magnification. If a control key is also depressed, the frame modifier may change in aspect ratio as the user “drags”, and new canvas choices may be displayed in a text window, not shown. 
     Specialized software  442  may be generated in common software program languages such as “C”, “Visual Basic”, and others well known in the field, and easily generated by those skilled in the art from software flow diagram  450  illustrated in FIG. 16, which depicts various functional blocks representing software code functions, hardware elements, and information pathways  452 . LAUNCH and INITIALIZATION  480  function includes normal application startup functions well known in the software field. Initialization may include a default software-generated image-guide size and shape, or may default to the previously used size and shape. SCENE SELECTION and CAPTURE  482  requests of the user to load into SCENE MEMORY  462  the desired scene from SCENE SOURCE MEMORY  460 , such as a CD, digital camera, video camera, internet connection, scanned scene, digitally drawn scene, and the like. 
     In WAIT STATE  509  the program awaits for a down-mouse button action in DETECT MOUSE DOWN &amp; POSITION  484 , or a DETECT ARROW KEY  486  action. As is typical in personal computer applications, various functions may be activated when the mouse position indicator, not shown, is over a specific region of the computer screen, such as a menu button or the image-guide frame. These are described for the following nine actions: 
     1. FILE  488  directs the program flow to store the current file to chosen memory not shown, or to print the computer screen from a sub-menu not shown, as is common in personal computer applications, illustrated in function STORE or PRINT  516  which stores or prints the combined scene and image-guide from the function COMBINE IMAGE-GUIDE WITH SCENE  514 . 
     2. ZOOM SCENE  490  directs the program to expand or compress the scene uniformly in horizontal and vertical dimensions for flexibility in use, followed by a scene update in UPDATE SCENE MEMORY  510 . 
     The following actions  3  through  9 , after performing their functions, direct the program to update the software-generated image-guide in UPDATE IMAGE-GUIDE VECTORS  512 . 
     3. CANVAS  492  directs the program to define the selected canvas size or aspect ratio from a sub-menu not shown containing the canvas and ruler information of Table II. 
     4. ZOOM FRAME  494  directs the program to expand or compress the software-generated image-guide in small steps, such as 2% steps or substantially continuous adjustment, to allow the user to adjust magnification from the scene to the canvas, as the user composes her image from the scene. 
     5. ORIENTATION  496  function rotates the software-generated image-guide for either landscape or portrait use. 
     6. SHOW GRIDS  498  toggles the grids within the image-guide frame on and off. Users may prefer composing their image in magnification and in translation with the grids and labels turned off, using the frame alone. 
     7. SHIFT FRAME  500  allows the user to position the mouse indicator over the frame and then, with the mouse-button held down, translate the frame horizontally and/or vertically to compose the image. 
     8. MODIFY FRAME  502  allows the user to position the mouse indicator over the composition frame modifier box and then, with the mouse-button held down, enlarge or shrink the composition frame to compose the image. If the control key, not shown, is detected, the aspect ratio of the composition frame may be changed as well by removing the constraint that changes in vertical and horizontal frame size remain proportional to the original frame dimensions. 
     9. HIGHLIGHT CELL  504  outlines the active cell with which the user is working with a bold square, a marquee, a colored square, a flashing outline, or the like to help user to keep track of the active cell. 
     In response to a DETECT ARROW KEY  486  occurrence when a user depresses one of the four keyboard arrow keys, not shown, the program flow is directed to CHANGE ACTIVE CELL  506  which may move the active cell selection in a direction according to the particular arrow key, as is commonly provided in personal computer applications. 
     Program flow from UPDATE SCENE MEMORY  510  or UPDATE IMAGE-GUIDE VECTORS  512  continues to the function COMBINE IMAGE-GUIDE WITH SCENE  514  wherein the image-guide is electronically overlayed onto the scene, and is then fed to ADD MENU &amp; MOUSE VIDEO  516  wherein the video information for DISPLAY SYSTEM  520  is combined. Following the updating of video information, the program flow returns to WAIT STATE  509 . TIMEOUT  508  may be triggered following 30 seconds, for example, of mouse-down condition, returning the program to WAIT STATE  509 . 
     The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.