From d19fe700f5e249d8f4b277004edcafe54fcc4106 Mon Sep 17 00:00:00 2001 From: GreaseMonkey Date: Thu, 23 Nov 2023 09:58:00 +1300 Subject: [PATCH] Use 8bpp renderer when attrregs.0x10.6 is set instead of when gdcreg.0x05.6 is set This allows correct emulation of the 4bpp chunky mode which is supported by many but not all chipsets. See discussion #3840 on GitHub. --- src/video/vid_svga.c | 125 ++++++++++++++++++++++++------------------- 1 file changed, 70 insertions(+), 55 deletions(-) diff --git a/src/video/vid_svga.c b/src/video/vid_svga.c index b2347f87c..1b9b3cf7c 100644 --- a/src/video/vid_svga.c +++ b/src/video/vid_svga.c @@ -639,67 +639,82 @@ svga_recalctimings(svga_t *svga) svga->hdisp *= (svga->seqregs[1] & 8) ? 16 : 8; svga->hdisp_old = svga->hdisp; - switch (svga->gdcreg[5] & 0x60) { - case 0x00: + if (svga->bpp <= 8) { + if (svga->attrregs[0x10] & 0x40) { /*8bpp mode*/ + svga->map8 = svga->pallook; + if (svga->lowres) /*Low res (320)*/ + svga->render = svga_render_8bpp_lowres; + else + svga->render = svga_render_8bpp_highres; + } else { if (svga->seqregs[1] & 8) /*Low res (320)*/ svga->render = svga_render_4bpp_lowres; else svga->render = svga_render_4bpp_highres; - break; - case 0x20: /*4 colours*/ - if (svga->seqregs[1] & 8) /*Low res (320)*/ - svga->render = svga_render_2bpp_lowres; - else - svga->render = svga_render_2bpp_highres; - break; - case 0x40: - case 0x60: /*256+ colours*/ - switch (svga->bpp) { - case 8: - svga->map8 = svga->pallook; - if (svga->lowres) - svga->render = svga_render_8bpp_lowres; - else - svga->render = svga_render_8bpp_highres; - break; - case 15: - if (svga->lowres) - svga->render = svga_render_15bpp_lowres; - else - svga->render = svga_render_15bpp_highres; - break; - case 16: - if (svga->lowres) - svga->render = svga_render_16bpp_lowres; - else - svga->render = svga_render_16bpp_highres; - break; - case 17: - if (svga->lowres) - svga->render = svga_render_15bpp_mix_lowres; - else - svga->render = svga_render_15bpp_mix_highres; - break; - case 24: - if (svga->lowres) - svga->render = svga_render_24bpp_lowres; - else - svga->render = svga_render_24bpp_highres; - break; - case 32: - if (svga->lowres) - svga->render = svga_render_32bpp_lowres; - else - svga->render = svga_render_32bpp_highres; - break; + } + } else { + switch (svga->gdcreg[5] & 0x60) { + case 0x00: + if (svga->seqregs[1] & 8) /*Low res (320)*/ + svga->render = svga_render_4bpp_lowres; + else + svga->render = svga_render_4bpp_highres; + break; + case 0x20: /*4 colours*/ + if (svga->seqregs[1] & 8) /*Low res (320)*/ + svga->render = svga_render_2bpp_lowres; + else + svga->render = svga_render_2bpp_highres; + break; + case 0x40: + case 0x60: /*256+ colours*/ + switch (svga->bpp) { + case 8: + svga->map8 = svga->pallook; + if (svga->lowres) + svga->render = svga_render_8bpp_lowres; + else + svga->render = svga_render_8bpp_highres; + break; + case 15: + if (svga->lowres) + svga->render = svga_render_15bpp_lowres; + else + svga->render = svga_render_15bpp_highres; + break; + case 16: + if (svga->lowres) + svga->render = svga_render_16bpp_lowres; + else + svga->render = svga_render_16bpp_highres; + break; + case 17: + if (svga->lowres) + svga->render = svga_render_15bpp_mix_lowres; + else + svga->render = svga_render_15bpp_mix_highres; + break; + case 24: + if (svga->lowres) + svga->render = svga_render_24bpp_lowres; + else + svga->render = svga_render_24bpp_highres; + break; + case 32: + if (svga->lowres) + svga->render = svga_render_32bpp_lowres; + else + svga->render = svga_render_32bpp_highres; + break; - default: - break; - } - break; + default: + break; + } + break; - default: - break; + default: + break; + } } } }