Add back dirty tiles optimization

2 files changed, 25 insertions, 57 deletions

diff --git a/src/main.c b/src/main.c
index 450a3cb..1dc5b5f 100644
--- a/src/main.c
+++ b/src/main.c
@@ -64,16 +64,21 @@
 //         txt_position((PROF_SHOW_X), (PROF_SHOW_Y)+3);\
 //         txt_printf("MIX:   %lu    ", mix_cycles);\
 //     } while (0)
+// #define PROF_SHOW() \
+//     do { \
+//         txt_position((PROF_SHOW_X), (PROF_SHOW_Y));\
+//         txt_printf("PIX:   %lu    ", ppu_pixel_cycles);\
+//         txt_position((PROF_SHOW_X), (PROF_SHOW_Y)+1);\
+//         txt_printf("1BPP:  %lu    ", ppu_icn_cycles);\
+//         txt_position((PROF_SHOW_X), (PROF_SHOW_Y)+2);\
+//         txt_printf("2BPP:  %lu    ", ppu_chr_cycles);\
+//         txt_position((PROF_SHOW_X), (PROF_SHOW_Y)+3);\
+//         txt_printf("FLIP:  %lu    ", flip_cycles);\
+//     } while (0)
 #define PROF_SHOW() \
     do { \
         txt_position((PROF_SHOW_X), (PROF_SHOW_Y));\
-        txt_printf("PIX:   %lu    ", ppu_pixel_cycles);\
-        txt_position((PROF_SHOW_X), (PROF_SHOW_Y)+1);\
-        txt_printf("1BPP:  %lu    ", ppu_icn_cycles);\
-        txt_position((PROF_SHOW_X), (PROF_SHOW_Y)+2);\
-        txt_printf("2BPP:  %lu    ", ppu_chr_cycles);\
-        txt_position((PROF_SHOW_X), (PROF_SHOW_Y)+3);\
-        txt_printf("FLIP:  %lu    ", flip_cycles);\
+        txt_printf("1BPP:  %lu    2BPP:  %lu", ppu_icn_cycles, ppu_chr_cycles);\
     } while (0)
 #define PROF_INIT() \
     static u32 ppu_pixel_cycles = 0;\
diff --git a/src/ppu.c b/src/ppu.c
index 96a3bc0..9937d95 100644
--- a/src/ppu.c
+++ b/src/ppu.c
@@ -310,6 +310,8 @@ ppu_1bpp(u32 *layer, u16 x, u16 y, u8 *sprite, u8 clr, u8 flip_x, u8 flip_y) {
     size_t start_row = y % 8;
     size_t shift_left = start_col * 4;
     size_t shift_right = (8 - start_col) * 4;
+    u32 dirtyflag = (1 << tile_x) | (1 << ((x + 7) >> 3));
+
     u32 *dst = &layer[start_row + (tile_x + tile_y * 32) * 8];
     u32 *lut = flip_x ? dec_byte_flip_x : dec_byte;
     if (blending[4][clr]) {
@@ -374,51 +376,11 @@ ppu_1bpp(u32 *layer, u16 x, u16 y, u8 *sprite, u8 clr, u8 flip_x, u8 flip_y) {
             }
         }
     }
-
-    // dirty_tiles[y >> 3] |= dirtyflag;
-    // dirty_tiles[(y + 7) >> 3] |= dirtyflag;
+    dirty_tiles[y >> 3] |= dirtyflag;
+    dirty_tiles[(y + 7) >> 3] |= dirtyflag;
 }
 #endif
 
-IWRAM_CODE
-static inline
-void
-draw_2bpp_row(void *layer, size_t x, size_t y, u8 a, u8 b, u8 flip_x) {
-    // BOUNDCHECK_SCREEN(x, y);
-
-    size_t tile_x = x / 8;
-    size_t tile_y = y / 8;
-    size_t start_col = x % 8;
-    size_t start_row = y % 8;
-    size_t shift_left = start_col * 4;
-    size_t shift_right = (8 - start_col) * 4;
-
-    u32 *dst = &layer[start_row + (tile_x + tile_y * 32) * 8];
-// #if DEC_BIG_LUT
-    u32 *lut = dec_byte;
-    if (flip_x) {
-        lut = dec_byte_flip_x;
-    }
-    u32 clr_a = lut[a];
-    u32 clr_b = lut[b];
-// #else
-//     u32 clr_a = decode_1bpp(a, flip_x);
-//     u32 clr_b = decode_1bpp(b, flip_x);
-// #endif
-    u32 mask_a = (clr_a * 0xF);
-    u32 mask_b = (clr_b * 0xF);
-    u32 mask = (mask_a | mask_b);
-    u32 color = clr_a + (clr_b << 1);
-    if (start_col == 0) {
-        dst[0] = (dst[0] & ~mask) | color;
-    } else {
-        dst[0] = (dst[0] & ~(mask << shift_left))  | (color << shift_left);
-        dst[8] = (dst[8] & ~(mask >> shift_right)) | (color >> shift_right);
-    }
-
-    // TODO: different blend modes?
-}
-
 #if NEW_PPU == 0
 IWRAM_CODE
 void
@@ -550,6 +512,7 @@ ppu_2bpp(u32 *layer, u16 x, u16 y, u8 *sprite, u8 clr, u8 flip_x, u8 flip_y) {
     size_t start_row = y % 8;
     size_t shift_left = start_col * 4;
     size_t shift_right = (8 - start_col) * 4;
+    u32 dirtyflag = (1 << tile_x) | (1 << ((x + 7) >> 3));
     u32 *dst = &layer[start_row + (tile_x + tile_y * 32) * 8];
     u32 *lut = flip_x ? dec_byte_flip_x : dec_byte;
     if (clr == 1) {
@@ -689,8 +652,8 @@ ppu_2bpp(u32 *layer, u16 x, u16 y, u8 *sprite, u8 clr, u8 flip_x, u8 flip_y) {
             }
         }
     }
-    // dirty_tiles[y >> 3] |= dirtyflag;
-    // dirty_tiles[(y + 7) >> 3] |= dirtyflag;
+    dirty_tiles[y >> 3] |= dirtyflag;
+    dirty_tiles[(y + 7) >> 3] |= dirtyflag;
 }
 #endif
 
@@ -712,20 +675,20 @@ flipbuf(Ppu *p) {
     Tile *mem_fg = FG_FRONT;
     Tile *mem_bg = BG_FRONT;
     for (size_t j = 0; j < 20; ++j) {
-        // if (dirty_tiles[j] == 0) {
-        //     continue;
-        // }
+        if (dirty_tiles[j] == 0) {
+            continue;
+        }
 
         size_t k = 1;
         for (size_t i = 0; i < 30; ++i, k <<= 1) {
-            // if (dirty_tiles[j] & k) {
+            if (dirty_tiles[j] & k) {
                 Tile *tile_fg = p->fg;
                 Tile *tile_bg = p->bg;
                 mem_fg[i + j * 32] = tile_fg[i + j * 32];
                 mem_bg[i + j * 32] = tile_bg[i + j * 32];
-            // }
+            }
         }
-        // dirty_tiles[j] = 0;
+        dirty_tiles[j] = 0;
     }
 }