paoda
/
zba
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

feat: fix tile flipping issue

This commit is contained in:
Rekai Nyangadzayi Musuka 2022-03-03 03:08:35 -04:00
parent 2e4854c2ff
commit c5b4b51ae0
1 changed files with 2 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
src/ppu.zig
View File

@ -102,13 +102,13 @@ pub const Ppu = struct {
// Calculate the Address of the Tile in the designated Charblock // Calculate the Address of the Tile in the designated Charblock
// We also take this opportunity to flip tiles if necessary // We also take this opportunity to flip tiles if necessary
const tile_id: u32 = entry.tile_id.read(); const tile_id: u32 = entry.tile_id.read();
const row = if (entry.h_flip.read()) 7 - (y % 8) else y % 8; // Determine on which row in a tile we're on const row = if (entry.v_flip.read()) 7 - (y % 8) else y % 8; // Determine on which row in a tile we're on
const tile_addr = char_base + (tile_len * tile_id) + (tile_row_offset * row); const tile_addr = char_base + (tile_len * tile_id) + (tile_row_offset * row);
// Calculate on which column in a tile we're on // Calculate on which column in a tile we're on
// Similarly to when we calculated the row, if we're in 4bpp we want to account // Similarly to when we calculated the row, if we're in 4bpp we want to account
// for 1 byte consisting of two pixels // for 1 byte consisting of two pixels
const col = if (entry.v_flip.read()) 7 - (x % 8) else x % 8; const col = if (entry.h_flip.read()) 7 - (x % 8) else x % 8;
const tile = self.vram.buf[tile_addr + if (is_8bpp) col else col / 2]; const tile = self.vram.buf[tile_addr + if (is_8bpp) col else col / 2];
// If we're in 8bpp, then the tile value is an index into the palette, // If we're in 8bpp, then the tile value is an index into the palette,