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improved sprite masking accuracy

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ekeeke31 2009-04-06 17:24:16 +00:00
parent 36e91c70aa
commit ae3ac87f7c
2 changed files with 48 additions and 20 deletions
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60
source/render.c
View File

@ -1619,6 +1619,8 @@ void parse_satb(uint32 line)
} }
} }
static int spr_over = 0;
static void render_obj(uint32 line, uint8 *buf, uint8 *table) static void render_obj(uint32 line, uint8 *buf, uint8 *table)
{ {
uint16 ypos; uint16 ypos;
@ -1642,21 +1644,27 @@ static void render_obj(uint32 line, uint8 *buf, uint8 *table)
uint8 palette; uint8 palette;
int attr_mask, nt_row; int attr_mask, nt_row;
int mask = 0;
for(count = 0; count < object_index_count; count += 1) for(count = 0; count < object_index_count; count += 1)
{ {
xpos = object_info[count].xpos & 0x1ff; xpos = object_info[count].xpos & 0x1ff;
/* sprite masking (low priority sprite only) */ /* sprite masking (ignore the 1st sprite) */
if(!xpos && count) return; if (xpos) spr_over = 1;
else if (spr_over)
{
spr_over = 0;
mask = 1;
}
size = object_info[count].size & 0x0f; size = object_info[count].size & 0x0f;
width = sizetab[(size >> 2) & 3]; width = sizetab[(size >> 2) & 3];
/* update pixel count (off-screen sprites included) */ /* update pixel count (off-screen sprites included) */
pixelcount += width; pixelcount += xpos ? width : (width * 2);
if(((xpos + width) >= left) && (xpos < right)) if(((xpos + width) >= left) && (xpos < right) && !mask)
{ {
ypos = object_info[count].ypos; ypos = object_info[count].ypos;
attr = object_info[count].attr; attr = object_info[count].attr;
@ -1676,7 +1684,11 @@ static void render_obj(uint32 line, uint8 *buf, uint8 *table)
/* number of tiles to draw */ /* number of tiles to draw */
/* adjusted for sprite limit */ /* adjusted for sprite limit */
if (pixelcount > bitmap.viewport.w) width -= (pixelcount - bitmap.viewport.w); if (pixelcount > bitmap.viewport.w)
{
width -= (pixelcount - bitmap.viewport.w);
}
width >>= 3; width >>= 3;
for(column = 0; column < width; column += 1, lb+=8) for(column = 0; column < width; column += 1, lb+=8)
@ -1685,13 +1697,17 @@ static void render_obj(uint32 line, uint8 *buf, uint8 *table)
src = &bg_pattern_cache[(index << 6) | (v_line)]; src = &bg_pattern_cache[(index << 6) | (v_line)];
DRAW_SPRITE_TILE; DRAW_SPRITE_TILE;
} }
} }
/* sprite limit (256 or 320 pixels) */ /* sprite limit (256 or 320 pixels) */
if (pixelcount >= bitmap.viewport.w) return; if (pixelcount >= bitmap.viewport.w)
{
spr_over = 1;
return;
}
} }
spr_over = 0;
} }
static void render_obj_im2(uint32 line, uint32 odd, uint8 *buf, uint8 *table) static void render_obj_im2(uint32 line, uint32 odd, uint8 *buf, uint8 *table)
@ -1718,21 +1734,27 @@ static void render_obj_im2(uint32 line, uint32 odd, uint8 *buf, uint8 *table)
uint32 offs; uint32 offs;
int attr_mask, nt_row; int attr_mask, nt_row;
int mask = 0;
for(count = 0; count < object_index_count; count += 1) for(count = 0; count < object_index_count; count += 1)
{ {
xpos = object_info[count].xpos & 0x1ff; xpos = object_info[count].xpos & 0x1ff;
/* sprite masking (low priority sprite only) */ /* sprite masking (ignore the 1st sprite) */
if(!xpos && count) return; if (xpos) spr_over = 1;
else if(spr_over)
{
spr_over = 0;
mask = 1;
}
size = object_info[count].size & 0x0f; size = object_info[count].size & 0x0f;
width = sizetab[(size >> 2) & 3]; width = sizetab[(size >> 2) & 3];
/* update pixel count (off-screen sprites included) */ /* update pixel count (off-screen sprites included) */
pixelcount += width; pixelcount += xpos ? width : (width * 2);
if(((xpos + width) >= left) && (xpos < right)) if(((xpos + width) >= left) && (xpos < right) && !mask)
{ {
ypos = object_info[count].ypos; ypos = object_info[count].ypos;
attr = object_info[count].attr; attr = object_info[count].attr;
@ -1766,7 +1788,13 @@ static void render_obj_im2(uint32 line, uint32 odd, uint8 *buf, uint8 *table)
} }
/* sprite limit (256 or 320 pixels) */ /* sprite limit (256 or 320 pixels) */
if (pixelcount >= bitmap.viewport.w) return; if (pixelcount >= bitmap.viewport.w)
{
spr_over = 1;
return;
}
} }
spr_over = 0;
} }

8
source/vdp.c
View File

@ -556,8 +556,8 @@ void vdp_ctrl_w(unsigned int data)
} }
else pending = 1; else pending = 1;
addr = ((addr_latch & 0xC000) | (data & 0x3FFF)) & 0xFFFF; addr = ((addr_latch & 0xC000) | (data & 0x3FFF));
code = ((code & 0x3C) | ((data >> 14) & 0x03)) & 0x3F; code = ((code & 0x3C) | ((data >> 14) & 0x03));
} }
else else
{ {
@ -565,8 +565,8 @@ void vdp_ctrl_w(unsigned int data)
pending = 0; pending = 0;
/* Update address and code registers */ /* Update address and code registers */
addr = ((addr & 0x3FFF) | ((data & 3) << 14)) & 0xFFFF; addr = ((addr & 0x3FFF) | ((data & 3) << 14));
code = ((code & 0x03) | ((data >> 2) & 0x3C)) & 0x3F; code = ((code & 0x03) | ((data >> 2) & 0x3C));
/* Save address bits A15 and A14 */ /* Save address bits A15 and A14 */
addr_latch = (addr & 0xC000); addr_latch = (addr & 0xC000);