-- https://docs.google.com/spreadsheets/d/1MU6K4c4PtMR_JXIpc3I0ZJdLZNnoFO7G2P3olCz6LSc
package ppu_consts is
	constant PPU_RAM_BUS_ADDR_WIDTH : natural := 16; -- RAM bus address width
	constant PPU_RAM_BUS_DATA_WIDTH : natural := 16; -- RAM bus data width
	constant PPU_FG_SPRITE_COUNT : natural := 128; -- amount of foreground sprites
	constant PPU_COLOR_OUTPUT_DEPTH : natural := 4; -- VGA output channel depth
	constant PPU_PALETTE_COLOR_WIDTH : natural := 3; -- palette index width (within sprite)
	constant PPU_PALETTE_INDEX_WIDTH : natural := 3; -- palette index width (palette table)
	constant PPU_PALETTE_CIDX_WIDTH : natural := PPU_PALETTE_COLOR_WIDTH + PPU_PALETTE_INDEX_WIDTH; -- global palette index width
	constant PPU_TMM_ADDR_WIDTH : natural := 16; -- tilemap memory ram bus address width
	constant PPU_TMM_DATA_WIDTH : natural := 15; -- tilemap memory ram bus data width
	constant PPU_BAM_ADDR_WIDTH : natural := 11; -- background attribute memory ram bus address width
	constant PPU_BAM_DATA_WIDTH : natural := 15; -- background attribute memory ram bus data width
	constant PPU_FAM_ADDR_WIDTH : natural := 8; -- foreground attribute memory ram bus address width
	constant PPU_FAM_DATA_WIDTH : natural := 16; -- foreground attribute memory ram bus data width
	constant PPU_PAL_ADDR_WIDTH : natural := 6; -- palette memory ram bus address width
	constant PPU_PAL_DATA_WIDTH : natural := 12; -- palette memory ram bus data width
	constant PPU_AUX_ADDR_WIDTH : natural := 1; -- auxiliary memory ram bus address width
	constant PPU_AUX_DATA_WIDTH : natural := 16; -- auxiliary memory ram bus data width
	constant PPU_POS_H_WIDTH : natural := 9; -- amount of bits for horizontal screen offset
	constant PPU_POS_V_WIDTH : natural := 8; -- amount of bits for vertical screen offset
	constant PPU_SPRITE_WIDTH : natural := 16; -- sprite width (pixels)
	constant PPU_SPRITE_HEIGHT : natural := 16; -- sprite height (pixels)
	constant PPU_SPRITE_POS_H_WIDTH: natural := 4; -- bits needed to identify horizontal pixel within sprite
	constant PPU_SPRITE_POS_V_WIDTH: natural := 4; -- bits needed to identify vertical pixel within sprite
	constant PPU_SCREEN_WIDTH : natural := 320; -- absolute screen width (pixels)
	constant PPU_SCREEN_HEIGHT : natural := 240; -- absolute screen height (pixels)
	constant PPU_BG_CANVAS_TILES_H : natural := 40; -- amount of tiles (horizontally) on background canvas
	constant PPU_BG_CANVAS_TILES_V : natural := 30; -- amount of tiles (vertically) on background canvas
	constant PPU_TILE_INDEX_WIDTH : natural := 10; -- amount of bits needed to index a tile from TMM memory
	constant PPU_PIXELS_PER_TILE_WORD : natural := 5; -- amount of pixels defined in one word in TMM memory
	constant PPU_SPRITE_PIXELS_PER_WORD : natural := 52; -- amount of words needed for a single sprite
end package ppu_consts;