Commodore 128D - Page 130

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Line 28 DRAWs the bottom window of the space capsule.
Line 35 DRAWs the top window of the space capsule. - -
Line 38 PAI NTs the space capsule white. 1—'
Line 40 DRAWs the outline of the retro rocket portion of the
spacecraft. r->
Line 42 and 43 DRAW the retro rocket engines on the back of Lj
the spacecraft.
Line 44 PAI NTs the retro rocket engines and DRAWs an out- ,—
line of the back of the retro rocket in the background color. LJ
Line 45 DRAWs lines on the retro rocket portion of the space
craft in the background color. (At this point, you have dis- — -
played only pictures on the screen. You have not used any w,
sprite statements, so your rocketship is not yet a sprite.)
Line 47 positions the SSHAPE coordinates above the first half —
(24 by 21 pixels), of the capsule of the spacecraft and stores it t j
in a data string, A$.
Line 48 positions the SSHAPE coordinates above the second
half (24 by 21 pixels) of the spacecraft and stores it in a data
string, B$.
Line 50 transfers the data from A$ into sprite 1.
Line 55 transfer the data from B$ into sprite 2.
Line 60 turns on sprite 1 and colors it red.
Line 65 turns on sprite 2 and colors it blue.
Line 82 positions sprite 1 at coordinate 150,150.
Line 83 positions sprite 2, 24 pixels to the right of the starting
coordinate of sprite 1.
Lines 82 and 83 actually join the two sprites.
Lines 85 and 87 moves the joined sprites across the screen.
Line 90 delays the program. This time, delay is necessary for - :
the sprites to complete three trips across the screen. If you j—I
leave out the delay, the sprites do not have enough time to
move across the screen. -• -
Lines 92 and 93 position the sprites in the center of the i >
screen, and prepare the spacecraft to fire the retro rockets.
Line 95 propels sprite 1, the space capsule, forward. The
number 10 in line 95 specifies the speed in which the sprite
moves. The speed ranges from 0, which is stop, to 15, which
is lightning fast.
Line 96 moves the expired retro rocket portion of the space
craft backwards and off the screen.
Line 97 is another time delay so the retro rocket, sprite 2, has
time to move off the screen.
Line 98 turns off sprite 2, once it is off the screen.
122 USING C128 MODE—Color, Animation and Sprite Graphics Statements >—I
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