valter/dosbox-staging
1
0
Fork 0
Code Releases Activity

Implement VGA memory wrapping for the wrapping line also in vgaonly rendering. Fixes black line in Keen.

Browse source 
Imported-from: https://svn.code.sf.net/p/dosbox/code-0/dosbox/trunk@3859
This commit is contained in:
Ralf Grillenberger 2014-06-08 00:00:53 +00:00
parent ee0367653b
commit 7f00bd4b34
1 changed files with 23 additions and 3 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

26
src/hardware/vga_draw.cpp
View file

@ -197,10 +197,30 @@ static Bit8u * VGA_Draw_Linear_Line(Bitu vidstart, Bitu /*line*/) {
}
static Bit8u * VGA_Draw_Xlat16_Linear_Line(Bitu vidstart, Bitu /*line*/) {
Bit8u *ret = &vga.draw.linear_base[ vidstart & vga.draw.linear_mask ];
Bitu offset = vidstart & vga.draw.linear_mask;
Bit8u *ret = &vga.draw.linear_base[offset];
Bit16u* temps = (Bit16u*) TempLine;
for(Bitu i = 0; i < vga.draw.line_length; i++) {
temps[i]=vga.dac.xlat16[ret[i]];
// see VGA_Draw_Linear_Line
if (GCC_UNLIKELY((vga.draw.line_length + offset)& ~vga.draw.linear_mask)) {
Bitu end = (offset + vga.draw.line_length) & vga.draw.linear_mask;
// assuming lines not longer than 4096 pixels
Bitu wrapped_len = end & 0xFFF;
Bitu unwrapped_len = vga.draw.line_length-wrapped_len;
// unwrapped chunk: to top of memory block
for(Bitu i = 0; i < unwrapped_len; i++)
temps[i]=vga.dac.xlat16[ret[i]];
// wrapped chunk: from base of memory block
for(Bitu i = 0; i < wrapped_len; i++)
temps[i + unwrapped_len]=vga.dac.xlat16[vga.draw.linear_base[i]];
} else {
for(Bitu i = 0; i < vga.draw.line_length; i++) {
temps[i]=vga.dac.xlat16[ret[i]];
}
}
return TempLine;
}