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                                                                EXHIBIT 10.20

                       AMENDMENT TO EMPLOYMENT AGREEMENT

     This agreement is made and entered into by and between SpatiaLight, Inc.
(the "Company") and L. John Loomis ("Loomis") as of September 19, 1997 (the
"Effective Date") with reference to the following facts:

     A.  On or about February 17, 1997, Loomis and the Company entered into
         an Employment Agreement, pursuant to which Loomis was initially
         employed by the Company as its Senior Executive Vice President and
         Chief Operating Officer, and later as its President and Chief
         Operating Officer (the "Employment Agreement");

     B.  The Company and Loomis now wish to amend the Employment Agreement as
         follows:

AMENDMENTS

     1.  Paragraph 2.3 of the Employment Agreement shall be struck in its
         entirety and replaced with the following language:

         2.3  EQUITY STAKE:  The Board has previously approved the issuance
              to Loomis of two separate options to purchase a total of
              520,000 shares of the Company's common stock (the "Options") in
              accordance with the Company's Stock Option Plan (the "Plan").
              The Plan provides that fifty percent of the options vest upon
              the completion of one year's service and the remaining fifty
              percent of the options vest upon the completion of the second
              year service.  However, in the event that the Company files
              for bankruptcy protection pursuant to the United States
              Bankruptcy Code, the parties have agreed that all of the
              options issued pursuant to the Option shall become fully vested
              as of the date the Company files its Petition for Bankruptcy
              Protection. The Options shall be further amended to provide
              that in the event of a Change of Control of the Company, all of
              the options issued pursuant to the Options shall become fully
              vested as of the date of the Change in Control.  A "Change in
              Control" is defined herein as a transaction or a series of
              related transactions resulting in the sale of all or
              substantially all of the Company's assets or a merger or
              consolidation, or sale or transfer of securities, which results
              in any entity which does not currently hold any of the
              outstanding voting securities of the Company (as determined
              immediately prior to such merger or consolidation or sale or
              transfer of stock) owning, directly or indirectly, thirty-three
              percent or more of the beneficial interest in the outstanding
              voting securities of the Company or the surviving corporation
              that controls the Company or of such surviving corporation's
              parent corporation (determined immediately after such merger or
              consolidation or sale or transfer of stock).  Except as
              otherwise provided herein, the Option shall be subject to the
              terms and conditions of the Company's stock option plan and the
              Company's standard form of stock option agreement, as amended
              in accordance with this Agreement, which Loomis shall be
              required to sign as a condition to receiving the Options as
              provided herein.

              ADDITIONAL OPTIONS:  After the occurrence of an equity
              financing during the nine months following the Effective Date
              in which the Company sells equity securities of the Company in
              an amount not less than Three Million Dollars ($3,000,000.00),
              Loomis shall be granted an additional stock option to purchase
              that number of shares of Common Stock determined by the
              following formula: the number of shares of the Company times
              four and one-third percent (4.33%) less the number of shares
              subject to options previously granted to Loomis.  If such
              formula produces a negative number, then Loomis shall not
              receive this Additional Option.  The exercise price of this
              option shall be

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              the fair market value at the time of the grant of the option.
              This Additional Option shall be immediately exercisable.

     2.  Paragraph 3 of the Employment Agreement shall be struck in its
         entirety and replaced with the following language:

     3.  TERM OF EMPLOYMENT:  Loomis' employment with the Company pursuant to
         this Agreement is for a five year period, commencing on the
         Commencement Date, subject to the provisions regarding termination
         set forth below (the "Term").  If neither party gives the other
         written notice of termination or a desire to change the provisions
         herein, this Agreement shall be automatically renewed for an
         additional one (1) year period (the "Renewal Term").  Thereafter, if
         neither party gives the other written notice of termination or a
         desire to change the provisions herein, on or before the thirtieth
         (30th) day prior to the expiration of each Renewal Term, this
         Agreement shall be renewed for an additional one (1) year period.

IN WITNESS WHEREOF, the parties have executed this Agreement as of the date
and year written below:

                                        SPATIALIGHT, INC.


Date:_____________________              By:__________________________________
                                        Its:_________________________________




Date:_____________________              _____________________________________
                                        L. John Loomis