smb 3041fps, life force 2058fps

1 files changed, 49 insertions, 115 deletions

diff --git a/mknes_ppu.c b/mknes_ppu.c
index 249f9f9..b00e380 100644
--- a/mknes_ppu.c
+++ b/mknes_ppu.c
@@ -279,132 +279,75 @@ static void ppu_tick(struct nes_state *state) {
 
 		if(rendering) {
 			if(scanline <= 239) {
-				if(dot >= 1 && dot <= 256) {
-					if(dot == 256) {
-						if((ppu->vram_addr & 0x7000) != 0x7000) {
-							ppu->vram_addr += 0x1000;
+				if(dot >= 1 && dot < 256) {	// NOTE(peter): dot 256 will be done in the next else in the chain
+					ppu_render_pixel(state, dot - 1, scanline, reg_mask);
+					goto shift_and_fetch;
+
+				} else if(dot == 256) {
+					if((ppu->vram_addr & 0x7000) != 0x7000) {
+						ppu->vram_addr += 0x1000;
+					} else {
+
+						ppu->vram_addr &= ~0x7000;
+						uint32_t y = (ppu->vram_addr & 0x03e0) >> 5;
+						if(y == 29) {
+							y = 0;
+							ppu->vram_addr ^= 0x0800;
+						} else if(y == 31) {
+							y = 0;
 						} else {
-
-							ppu->vram_addr &= ~0x7000;
-							uint32_t y = (ppu->vram_addr & 0x03e0) >> 5;
-							if(y == 29) {
-								y = 0;
-								ppu->vram_addr ^= 0x0800;
-							} else if(y == 31) {
-								y = 0;
-							} else {
-								y++;
-							}
-							ppu->vram_addr = (ppu->vram_addr & ~0x03e0) | (y << 5);
+							y++;
 						}
+						ppu->vram_addr = (ppu->vram_addr & ~0x03e0) | (y << 5);
 					}
-
 					ppu_render_pixel(state, dot - 1, scanline, reg_mask);
-					goto stupid;
-				}
+					goto shift_and_fetch;
 
-				if(dot == 257) {
+				} else if(dot == 257) {
 					ppu->vram_addr = (ppu->vram_addr & ~0x041f) | (ppu->temp_addr & 0x041f);
 					ppu_evaluate_sprites(state, scanline);
-				}
-
-				if(dot >= 321 && dot <= 336) {
-stupid:			if(reg_mask & PPU_MASK_SHOW_SPRITES) {
-						for(uint32_t i = 0; i < ppu->sprite_count; i++) {
-							if(ppu->sprites[i].position > 0) {
-								ppu->sprites[i].position--;
-							} else {
-								ppu->sprites[i].shift_lo <<= 1;
-								ppu->sprites[i].shift_hi <<= 1;
-							}
-						}
-					}
-
-					ppu->bg_shift_pattern_low <<= 1;
-					ppu->bg_shift_pattern_high <<= 1;
-					ppu->bg_shift_attrib_low <<= 1;
-					ppu->bg_shift_attrib_high <<= 1;
 
-					switch(dot % 8) {
-						case 1: {
-							uint32_t nt_addr = 0x2000 | (ppu->vram_addr & 0x0fff);
-							ppu->bg_next_tile_id = state->mapper_function.ciram_read(state, nt_addr);
-						} break;
-
-						case 3: {
-							uint32_t attr_addr = 0x23c0 | (ppu->vram_addr & 0x0c00) | ((ppu->vram_addr >> 4) & 0x38) | ((ppu->vram_addr >> 2) & 0x07);
-							uint8_t attr = state->mapper_function.ciram_read(state, attr_addr & 0x0fff);
-							uint8_t shift = ((ppu->vram_addr >> 4) & 4) | (ppu->vram_addr & 2);
-							ppu->bg_next_tile_attrib = (attr >> shift) & 3;
-						} break;
-
-						case 5: {
-							uint32_t base = (ppu->reg_ctrl & PPU_CTRL_BG_TILE_SELECT) << 8;
-							uint32_t tile = ppu->bg_next_tile_id;
-							uint32_t fine_y = (ppu->vram_addr >> 12) & 7;
-							uint32_t addr_lsb = (base + tile * 16 + fine_y) & 0x1fff;
-							ppu->bg_next_tile_lsb = state->mapper_function.chr_read(state, addr_lsb);
-						} break;
+				} else if(dot >= 321 && dot <= 336) {
+					goto shift_and_fetch;
 
-						case 7: {
-							uint32_t base = (ppu->reg_ctrl & PPU_CTRL_BG_TILE_SELECT) << 8;
-							uint32_t tile = ppu->bg_next_tile_id;
-							uint32_t fine_y = (ppu->vram_addr >> 12) & 7;
-							uint32_t addr_msb = (base + tile * 16 + fine_y + 8) & 0x1fff;
-							ppu->bg_next_tile_msb =  state->mapper_function.chr_read(state, addr_msb);
-						} break;
-
-						case 0: {
-							ppu->bg_shift_pattern_low = (ppu->bg_shift_pattern_low) | ppu->bg_next_tile_lsb;
-							ppu->bg_shift_pattern_high = (ppu->bg_shift_pattern_high) | ppu->bg_next_tile_msb;
-
-							uint8_t a = ppu->bg_next_tile_attrib;
-							ppu->bg_shift_attrib_low = (ppu->bg_shift_attrib_low) | ((a & 1) ? 0xff : 0x00);
-							ppu->bg_shift_attrib_high = (ppu->bg_shift_attrib_high) | ((a & 2) ? 0xff : 0x00);
-
-							if((ppu->vram_addr & 0x001f) == 31) {
-								ppu->vram_addr &= ~0x001f;
-								ppu->vram_addr ^= 0x0400;
-							} else {
-								ppu->vram_addr++;
-							}
-						} break;
-					}
-				}
-
-				if(dot == 340) {
+				} else if(dot == 340) {
 					ppu_fetch_sprite_patterns(state, scanline);
 				}
-
 			}
 
 			if(scanline == 261) {
 
-				if(dot >= 1 && dot <= 256) {
-					if(dot == 256) {
-						if((ppu->vram_addr & 0x7000) != 0x7000) {
-							ppu->vram_addr += 0x1000;
+				if(dot >= 1 && dot < 256) {	// NOTE(peter): dot 256 will be done in the next else in the chain
+					goto shift_and_fetch;
+
+				} else if(dot == 256) {
+					if((ppu->vram_addr & 0x7000) != 0x7000) {
+						ppu->vram_addr += 0x1000;
+					} else {
+
+						ppu->vram_addr &= ~0x7000;
+						uint32_t y = (ppu->vram_addr & 0x03e0) >> 5;
+						if(y == 29) {
+							y = 0;
+							ppu->vram_addr ^= 0x0800;
+						} else if(y == 31) {
+							y = 0;
 						} else {
-
-							ppu->vram_addr &= ~0x7000;
-							uint32_t y = (ppu->vram_addr & 0x03e0) >> 5;
-							if(y == 29) {
-								y = 0;
-								ppu->vram_addr ^= 0x0800;
-							} else if(y == 31) {
-								y = 0;
-							} else {
-								y++;
-							}
-							ppu->vram_addr = (ppu->vram_addr & ~0x03e0) | (y << 5);
+							y++;
 						}
+						ppu->vram_addr = (ppu->vram_addr & ~0x03e0) | (y << 5);
 					}
+					goto shift_and_fetch;
 
-					goto stupid2;
-				}
+				} else if(dot == 257) {
+					ppu->vram_addr = (ppu->vram_addr & ~0x041f) | (ppu->temp_addr & 0x041f);
+
+				} else if(dot >= 280 && dot <= 304) {
+					ppu->vram_addr = (ppu->vram_addr & ~0x7be0) | (ppu->temp_addr & 0x7be0);
 
-				if(dot >= 321 && dot <= 336) {
-stupid2:			if(reg_mask & PPU_MASK_SHOW_SPRITES) {
+				} else if(dot >= 321 && dot <= 336) {
+shift_and_fetch:
+					if(reg_mask & PPU_MASK_SHOW_SPRITES) {
 						for(uint32_t i = 0; i < ppu->sprite_count; i++) {
 							if(ppu->sprites[i].position > 0) {
 								ppu->sprites[i].position--;
@@ -420,7 +363,6 @@ stupid2:			if(reg_mask & PPU_MASK_SHOW_SPRITES) {
 					ppu->bg_shift_attrib_low <<= 1;
 					ppu->bg_shift_attrib_high <<= 1;
 
-
 					switch(dot % 8) {
 						case 1: {
 							uint32_t nt_addr = 0x2000 | (ppu->vram_addr & 0x0fff);
@@ -467,14 +409,6 @@ stupid2:			if(reg_mask & PPU_MASK_SHOW_SPRITES) {
 						} break;
 					}
 				}
-
-				if(dot == 257) {
-					ppu->vram_addr = (ppu->vram_addr & ~0x041f) | (ppu->temp_addr & 0x041f);
-				}
-
-				if(dot >= 280 && dot <= 304) {
-					ppu->vram_addr = (ppu->vram_addr & ~0x7be0) | (ppu->temp_addr & 0x7be0);
-				}
 			}
 		}