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Daedalus · 05 November 2019, 22:36

You can do it very easily by drawing directly to shapes (ShapesBitMap, MakeCookie), then transferring the image data to the sprite using GetaSprite. This copies the image data, so it's not entirely efficient, but if it's a relatively small amount of information the time taken should be minimal.

I haven't tried it, but to actually draw directly to the sprite image data, you could use CludgeBitmap, which sets up a bitmap object but doesn't allocate any memory for it. Instead, you give it a pointer to already-allocated memory, such as manually decoded image data, or the bitmap of a sprite.

Code:

myBitMap.l = Peek.l(ADDR Sprite 0)
CludgeBitmap 0, 16, 16, 2, myBitMap

should give you the image data pointer, then create bitmap object ID 0 (16x16, 4 colour) at that location, allowing you to draw to it at will. Bear in mind that that will update in realtime on the screen, so you might want to synchronise your drawing with VWait.

05 November 2019, 22:36	#6
Daedalus Registered User Join Date: Jun 2009 Location: Dublin, then Glasgow Posts: 6,343	You can do it very easily by drawing directly to shapes (ShapesBitMap, MakeCookie), then transferring the image data to the sprite using GetaSprite. This copies the image data, so it's not entirely efficient, but if it's a relatively small amount of information the time taken should be minimal. I haven't tried it, but to actually draw directly to the sprite image data, you could use CludgeBitmap, which sets up a bitmap object but doesn't allocate any memory for it. Instead, you give it a pointer to already-allocated memory, such as manually decoded image data, or the bitmap of a sprite. Code: myBitMap.l = Peek.l(ADDR Sprite 0) CludgeBitmap 0, 16, 16, 2, myBitMap should give you the image data pointer, then create bitmap object ID 0 (16x16, 4 colour) at that location, allowing you to draw to it at will. Bear in mind that that will update in realtime on the screen, so you might want to synchronise your drawing with VWait.