XGA
eXtended Graphics Accelerator
4 featured screen modes
mode 0: 256x212, 8/16bpp, pixmap graphic, pattern and sprite layers.
mode 1: 320x240, 8/16bpp, pixmap graphic, pattern and sprite layers.
mode 2: 512x424, 8/16bpp, pixmap graphics and pattern layers.
mode 3: 640x480, 8/16bpp, pixmap graphics and pattern layers.
THE PROTOTYPE BOARD
Multiple layers
maximum 6 layers
pixmap graphics layers (16bpp support)
pixmap or bitmap pattern layers
8/16 bit pattern name support
sprite layers
Sprite
maximum 240 sprites can be displayed simultaneously with a priority
8 bpp pixmap patterns. 1024 16x16 patterns or 256 32x32 patterns.
9-bit co-ordinate system
features: palette change, wrap around, grouping and sticking to pattern layers.
Command
fill box
copy
line
draw
bitmap to pixmap
and more
Etc
each layer scrollable in x-y directions
256 15-bit width color palettes
9/10-bit co-ordinate system
variable sized bitmap text
4MB memory / VGA output
Pattern layer
maximum 2 seperate layers
16-bit pattern name with attributes
8x8, 16x8, 8x16, 16x16 sized 8bpp pattern.
128x64 tile space (max 2048x1024 in pixel space)
features: blinking and more.
Helper fuction for lazy programers
sprite visibility detection
sprite positioning (collision detection)
and more