Update qtcreator.md

Use buildDir env var instead of hardcoded paths to mkvogl.
Fix a few typos.
UI: Improve processing time of vogleditor_apicalltreeitem by pre-calculating the local row index
* This value will have to get updated if new rows (API calls) can be added / removed, which may undo this optimization,
but when investigating a slowness during searching, the code was often found in this function.
UI: Fix issue #20: Search in the editor really slow
* Instead of selecting all the rows which match the search string,
  the tree view now highlights those rows which match and are visible.
* If the user presses [enter], the first matching row (if one exists) will
  be scrolled into view and selected.
* Continually pressing enter will cycle through each match, in the same way
  that clicking the "Next" button works.
* If there are no matching items when the user presses [enter], the background to the search textbox will turn red.
  It will restore to its previous color when the user next edits the text.
Merge branch 'master' of https://github.com/PeterLValve/vogl
Merge pull request #24 from PeterLValve/master

Fix issue #20: Search in the editor really slow; minor doc improvements
Merge pull request #23 from kingtaurus/master

Proposed changes to fix issue #16.
UI: Fix issue #21: Resizing of vogleditor window is slow depending on trace size
* If the window is only being resized a small amount (within 20%), the timeline will no longer redraw and simply gets stretched.
* When the timeline is redrawn, it will now only draw one timeline item per pixel instead of many sub-pixel items.
* Fixed an issue that caused 0-duration items from being scaled to 1 instead of the horizontal scale value (which should be the minimum amount of time needed to appear as a single pixel). This greatly reduced the number of items being drawn.
* Fixed deletion of timeline item children.

* These improvements reduced the number of drawn items in one particular trace file from ~5.9 million, down to ~1250 in the default window size. When I stretched the editor across two monitors (giving the timeline more pixels to draw into) this increased to ~4500 items - both very reasonable numbers.
Merge pull request #27 from PeterLValve/master

UI: Fix issue #21: Resizing of vogleditor window is slow depending on trace size
- Fixing polygon stipple saving/restoring so it doesn't stomp memory after the polygon stipple object (whoops!)
- Fixing driver crash on AMD's fglrx caused by us passing down possibly bogus handles when we fail to remote program uniform's (which commonly happens when we trace on NVidia and try to replay on AMD, which more aggressively optimizes uniforms).
Fixing various issues that were showing up when trying to snapshot/restore Cube 2:
- RBO's which have been genned but never initialized are now properly snapshotted/restored
- Adding support for GL_FLOAT_RG16_NV
- Fixing size of XVisualInfo struct's ctype desc so the --find command doesn't trigger a harmless but annoying assert in 32-bit builds while scanning through 64-bit traces
- Misc help text fixes
Fixing various issues that were showing up when trying to snapshot/restore Cube 2:
- RBO's which have been genned but never initialized are now properly snapshotted/restored
- Adding support for GL_FLOAT_RG16_NV
- Fixing size of XVisualInfo struct's ctype desc so the --find command doesn't trigger a harmless but annoying assert in 32-bit builds while scanning through 64-bit traces
- Misc help text fixes
- Fix for restoring FBO's that have attachments that the tracer was not able to query (because they were deleted). Steam 10ft keeps a bunch of FBO's around with deleted textures in a cache. It eventually rebinds new textures to the FBO's so the fact that we can't query the texture shouldn't be an issue (for 10ft anyway).
Update README.md

A trace file can be passed to vogleditor on the command line to have it loaded automatically.
Update qtcreator.md

Add information about launching and debugging projects from within QtCreator since the default Run configuration is not valid.
Fixing issue #32.
Added a check of SDL_GLContext;

src/gltests/include/testcommon.h:
  (1) added assert header when enabling debugging (check is on NDEBUG not being defined);

src/gltests/core-vao/main.c
src/gltests/fixedfunc-multitexcoord-2d/main.c
src/gltests/msaa_depthstencil/main.c
src/gltests/texture-array-1d/main.c
src/gltests/texture-array-2d-msaa/main.c
src/gltests/texture-array-2d/main.c
src/gltests/texture-array-nonzerobase/main.c
src/gltests/texture-array-subimages/main.c
src/gltests/texture-nonzerobase/main.c
  (1) added an assert on the SDL_GLContext being valid;
      why: Open source drivers currently support up to specific OpenGL context
           - so fail early (in order to avoid failure later in the code);