Sprites do not have exclusive use of the color registers. The following figure shows which color registers are used by Simple Sprites. See "VSprite Advanced Topics" later in this chapter, for precautions to take if Simple Sprites and VSprites are used at the same time. The Sprite pairs 0/1, 2/3, 4/5, and 6/7 share color registers. (That is, if you create a Simple Sprite relative to your ViewPort and move the ViewPort around, the Simple Sprite can move as well, but its movement is relative to the origin of the ViewPort.) Unlike VSprites, the motion of a Simple Sprite can be relative to this position. The upper left corner of the ViewPort area has coordinates (0,0). The same sprite image data is placed into both even and odd fields of the interlaced display, so the sprite will appear to be the same size in any display mode. Similarly, in an interlaced display, the y direction motions are in two-line increments. In low-resolution mode, a single Lores pixel movement will be seen. If the sprite is being moved across a high-resolution display in single pixel increments, it will appear to move two high-resolution pixels for each increment. Currently, sprites always appear as low-resolution pixels, and their position is specified in the same way. Simple Sprites are always 16 bits wide, which is why there is no width member in the SimpleSprite structure. It has fields that indicate the height and position of the Simple Sprite and a number that indicates which of the 8 hardware sprites to use. For more information on the sprite hardware, including information on attached sprites, see the Amiga Hardware Reference Manual. ![]() Simple Sprites can be used to create animations, so even though are not really part of the GELs system, they are described here as a possible alternative to using VSprites. 1.1.2 Changing The Appearance Of A Simple Sprite.
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