This webpage renders the screens of CoCo graphical adventures by decoding the data and displaying it, both as pmode 4 black & white, and as simulated ntsc artifact colors.
The main part of this program is the 'decode' function which like the assembly version decodes the compressed data of the game into a stream of pixels.
Each adventure screen contains 1 of 6 background screens and then a number of overlays are pasted on top. Each screen is described by the SCRIND array, the first element is the background screen used, indexed into SCREENS, and the rest are the overlays.
Each overlay has a compressed data stream and a position where it beings drawing contained in SCROBJ.
Additionally the data for game objects is included however as it depends on your inventory only the base objects are displayed.
Click here to View Program
The following keys will switch to different adventure game:
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A - Sea Quest
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B - Calixto Island
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C - Shenanigans
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D - Black Sanctum
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E - Trekboer
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Pad4 & Pad6 - decrement/increment the room number displayed.
Clicking the mouse in the area above the palette will enlarge the dot pattern being rendered.
The X position of the mouse when below the palette will render n pixels. Moving the mouse left and right in this area will show how the game would render the images.