Initial stab at horizontal border emulation. Only works for H40 and still has a few minor holes to fill

4 files changed, 52 insertions, 15 deletions

diff --git a/default.cfg b/default.cfg
index 7a5edcd..0ff4e37 100644
--- a/default.cfg
+++ b/default.cfg
@@ -147,6 +147,10 @@ video {
 			#comment out those two lines and uncomment these
 			#top 11
 			#bottom 8
+			
+			#these values will completely hide the horizontal border
+			left 13
+			right 14
 		}
 	}
 	pal {
@@ -161,6 +165,10 @@ video {
 			#coment out those two lines and uncomment these
 			#top 30
 			#bottom 24
+			
+			#these values will completely hide the horizontal border
+			left 13
+			right 14
 		}
 	}
 }
diff --git a/render_sdl.c b/render_sdl.c
index e0fe476..b0a0fa3 100755
--- a/render_sdl.c
+++ b/render_sdl.c
@@ -256,7 +256,7 @@ static void render_alloc_surfaces()
 #endif
 		
 		//TODO: Fixme for invalid display mode
-		sdl_textures[0] = sdl_textures[1] = SDL_CreateTexture(main_renderer, SDL_PIXELFORMAT_ARGB8888, SDL_TEXTUREACCESS_STREAMING, 320, 588);
+		sdl_textures[0] = sdl_textures[1] = SDL_CreateTexture(main_renderer, SDL_PIXELFORMAT_ARGB8888, SDL_TEXTUREACCESS_STREAMING, LINEBUF_SIZE, 588);
 #ifndef DISABLE_OPENGL
 	}
 #endif
@@ -324,6 +324,8 @@ static void update_aspect()
 
 static uint32_t overscan_top[NUM_VID_STD] = {2, 21};
 static uint32_t overscan_bot[NUM_VID_STD] = {1, 17};
+static uint32_t overscan_left[NUM_VID_STD] = {13, 13};
+static uint32_t overscan_right[NUM_VID_STD] = {14, 14};
 static vid_std video_standard = VID_NTSC;
 static char *vid_std_names[NUM_VID_STD] = {"ntsc", "pal"};
 void render_init(int width, int height, char * title, uint8_t fullscreen)
@@ -375,6 +377,14 @@ void render_init(int width, int height, char * title, uint8_t fullscreen)
 				if (val) {
 					overscan_bot[i] = atoi(val);
 				}
+				val = tern_find_path_default(std_settings, "overscan\0left\0", (tern_val){.ptrval = NULL}).ptrval;
+				if (val) {
+					overscan_left[i] = atoi(val);
+				}
+				val = tern_find_path_default(std_settings, "overscan\0right\0", (tern_val){.ptrval = NULL}).ptrval;
+				if (val) {
+					overscan_right[i] = atoi(val);
+				}
 			}
 		}
 	}
@@ -504,7 +514,7 @@ uint32_t *render_get_framebuffer(uint8_t which, int *pitch)
 {
 #ifndef DISABLE_OPENGL
 	if (render_gl && which <= FRAMEBUFFER_EVEN) {
-		*pitch = 320 * sizeof(uint32_t); //TODO: change this to LINEBUF_SIZE once border rendering is added
+		*pitch = LINEBUF_SIZE * sizeof(uint32_t);
 		return texture_buf;
 	} else {
 #endif
@@ -548,6 +558,7 @@ void render_framebuffer_updated(uint8_t which, int width)
 	uint32_t height = which <= FRAMEBUFFER_EVEN 
 		? (video_standard == VID_NTSC ? 243 : 294) - (overscan_top[video_standard] + overscan_bot[video_standard])
 		: 240;
+	width -= overscan_left[video_standard] + overscan_right[video_standard];
 	FILE *screenshot_file = NULL;
 	uint32_t shot_height;
 	if (screenshot_path && which == FRAMEBUFFER_ODD) {
@@ -564,7 +575,7 @@ void render_framebuffer_updated(uint8_t which, int width)
 #ifndef DISABLE_OPENGL
 	if (render_gl && which <= FRAMEBUFFER_EVEN) {
 		glBindTexture(GL_TEXTURE_2D, textures[which]);
-		glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 320, height, GL_BGRA, GL_UNSIGNED_BYTE, texture_buf + 320 * overscan_top[video_standard]);
+		glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, width, height, GL_BGRA, GL_UNSIGNED_BYTE, texture_buf + overscan_left[video_standard] + LINEBUF_SIZE * overscan_top[video_standard]);
 
 		glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
 		glClear(GL_COLOR_BUFFER_BIT);
@@ -594,7 +605,7 @@ void render_framebuffer_updated(uint8_t which, int width)
 		
 		if (screenshot_file) {
 			//properly supporting interlaced modes here is non-trivial, so only save the odd field for now
-			save_ppm(screenshot_file, texture_buf, width, shot_height, 320*sizeof(uint32_t));
+			save_ppm(screenshot_file, texture_buf, width, shot_height, LINEBUF_SIZE*sizeof(uint32_t));
 		}
 	} else {
 #endif
@@ -625,7 +636,7 @@ void render_framebuffer_updated(uint8_t which, int width)
 		}
 		SDL_UnlockTexture(sdl_textures[which]);
 		SDL_Rect src_clip = {
-			.x = 0,
+			.x = overscan_left[video_standard],
 			.y = overscan_top[video_standard],
 			.w = width,
 			.h = height
diff --git a/vdp.c b/vdp.c
index d69fe81..54bb7e2 100644
--- a/vdp.c
+++ b/vdp.c
@@ -711,8 +711,8 @@ static void read_sprite_x_mode4(vdp_context * context)
 #define VSRAM_BITS 0x7FF
 #define VSRAM_DIRTY_BITS 0xF800
 
-//rough estimate of slot number at which active display starts
-#define BG_START_SLOT 9
+//rough estimate of slot number at which border display starts
+#define BG_START_SLOT 0
 
 void write_cram(vdp_context * context, uint16_t address, uint16_t value)
 {
@@ -733,7 +733,7 @@ void write_cram(vdp_context * context, uint16_t address, uint16_t value)
 		context->vcounter < context->inactive_start + context->border_bot 
 		|| context->vcounter > 0x200 - context->border_top
 	)) {
-		uint8_t bg_end_slot = BG_START_SLOT + (context->regs[REG_MODE_4] & BIT_H40) ? 320/2 : 256/2;
+		uint8_t bg_end_slot = BG_START_SLOT + (context->regs[REG_MODE_4] & BIT_H40) ? LINEBUF_SIZE/2 : (256+HORIZ_BORDER)/2;
 		if (context->hslot < bg_end_slot) {
 			uint32_t color = (context->regs[REG_MODE_2] & BIT_MODE_5) ? context->colors[addr] : context->colors[addr + CRAM_SIZE*3];
 			context->output[(context->hslot - BG_START_SLOT)*2 + 1] = color;
@@ -1204,7 +1204,7 @@ static void render_map_output(uint32_t line, int32_t col, vdp_context * context)
 	if (col)
 	{
 		col-=2;
-		dst = context->output + col * 8;
+		dst = context->output + BORDER_LEFT + col * 8;
 		if (context->debug < 2) {
 			sprite_buf = context->linebuf + col * 8;
 			uint8_t a_src, src;
@@ -1486,7 +1486,7 @@ static void vdp_advance_line(vdp_context *context)
 		context->vcounter &= 0x1FF;
 	} else {
 		if (context->vcounter == context->inactive_start) {
-			render_framebuffer_updated(context->flags2 & FLAG2_EVEN_FIELD ? FRAMEBUFFER_EVEN: FRAMEBUFFER_ODD, context->h40_lines > (context->inactive_start + context->border_top) / 2 ? 320 : 256);
+			render_framebuffer_updated(context->flags2 & FLAG2_EVEN_FIELD ? FRAMEBUFFER_EVEN: FRAMEBUFFER_ODD, context->h40_lines > (context->inactive_start + context->border_top) / 2 ? LINEBUF_SIZE : (256+HORIZ_BORDER));
 			if (context->double_res) {
 				context->flags2 ^= FLAG2_EVEN_FIELD;
 			}
@@ -1528,6 +1528,12 @@ static void vdp_advance_line(vdp_context *context)
 		read_map_scroll_a(column, context->vcounter, context);\
 		CHECK_LIMIT\
 	case ((startcyc+1)&0xFF):\
+		if (column == 2) {\
+			uint32_t bg_color = context->colors[context->regs[REG_BG_COLOR] & 0x3F];\
+			for (int i = 0; i < BORDER_LEFT; i++) {\
+				context->output[i] = bg_color;\
+			}\
+		}\
 		external_slot(context);\
 		CHECK_LIMIT\
 	case ((startcyc+2)&0xFF):\
@@ -1838,9 +1844,15 @@ static void vdp_h40(vdp_context * context, uint32_t target_cycles)
 	case 161:
 		external_slot(context);
 		CHECK_LIMIT
-	case 162:
+	case 162: {
 		external_slot(context);
+		uint32_t bg_color = context->colors[context->regs[REG_BG_COLOR] & 0x3F];
+		for (int i = LINEBUF_SIZE-BORDER_RIGHT; i < LINEBUF_SIZE; i++)
+		{
+			context->output[i] = bg_color;
+		}
 		CHECK_LIMIT
+	}
 	//sprite render to line buffer starts
 	case 163:
 		context->cur_slot = MAX_DRAWS-1;
@@ -2199,7 +2211,7 @@ static void vdp_inactive(vdp_context *context, uint32_t target_cycles, uint8_t i
 		if (is_h40) {
 			buf_clear_slot = 161;
 			index_reset_slot = 165;
-			bg_end_slot = BG_START_SLOT + 320/2;
+			bg_end_slot = BG_START_SLOT + LINEBUF_SIZE/2;
 			max_draws = MAX_DRAWS-1;
 			max_sprites = MAX_SPRITES_LINE;
 			index_reset_value = 0x80;
@@ -2208,7 +2220,7 @@ static void vdp_inactive(vdp_context *context, uint32_t target_cycles, uint8_t i
 			jump_start = 182;
 			jump_dest = 229;
 		} else {
-			bg_end_slot = BG_START_SLOT + 256/2;
+			bg_end_slot = BG_START_SLOT + (256+HORIZ_BORDER)/2;
 			max_draws = MAX_DRAWS_H32-1;
 			max_sprites = MAX_SPRITES_LINE_H32;
 			buf_clear_slot = 128;
@@ -2222,7 +2234,7 @@ static void vdp_inactive(vdp_context *context, uint32_t target_cycles, uint8_t i
 		vint_line = context->inactive_start;
 		active_line = 0x1FF;
 	} else {
-		bg_end_slot = BG_START_SLOT + 256/2;
+		bg_end_slot = BG_START_SLOT + (256+HORIZ_BORDER)/2;
 		max_draws = MAX_DRAWS_H32_MODE4;
 		buf_clear_slot = 136;
 		index_reset_slot = 253;
@@ -2277,6 +2289,9 @@ static void vdp_inactive(vdp_context *context, uint32_t target_cycles, uint8_t i
 			}
 			*(dst++) = bg_color;
 			*(dst++) = bg_color;
+			if (context->hslot == (bg_end_slot-1)) {
+				*(dst++) = bg_color;
+			}
 		}
 		
 		if (!is_refresh(context, context->hslot)) {
diff --git a/vdp.h b/vdp.h
index 72b45c5..e51a3fa 100644
--- a/vdp.h
+++ b/vdp.h
@@ -14,7 +14,10 @@
 #define CRAM_SIZE 64
 #define VSRAM_SIZE 40
 #define VRAM_SIZE (64*1024)
-#define LINEBUF_SIZE (320+27) //H40 + full border
+#define BORDER_LEFT 13
+#define BORDER_RIGHT 14
+#define HORIZ_BORDER (BORDER_LEFT+BORDER_RIGHT)
+#define LINEBUF_SIZE (320+HORIZ_BORDER) //H40 + full border
 #define BORDER_BOTTOM 13 //TODO: Replace with actual value
 #define MAX_DRAWS 40
 #define MAX_DRAWS_H32 32