mirror/86Box
1
0
Fork 0
mirror of https://github.com/86Box/86Box.git synced 2026-02-22 17:45:31 -07:00
Code Issues Packages Projects Releases Activity

Defer vsync_offset application

Browse Source 
- Apply vsync_offset only during the vertical retrace period for a more accurate result
- Change the calculation of displine_offs and remove redundant checks around rendering calls
- Remove unnecessary clamping logic for crtc[7]
- Remove a hack from the previous commit by correctly triggering VSYNC processing when the vertical counter matches the actual crtc[7]
This commit is contained in:
pixel-jupiter
2025-10-03 16:44:53 +03:00
parent 49a3eca742
commit beb3733757
2 changed files with 21 additions and 34 deletions
Download Patch File Download Diff File Expand all files Collapse all files

1
src/include/86box/m_tandy.h
View File

@@ -41,6 +41,7 @@ typedef struct t1kvid_t {
bool baseline_ready;
int hsync_offset;
int vsync_offset;
int vsync_offset_pending;
int linepos;
int displine;

54
src/video/vid_tandy.c
View File

@@ -199,11 +199,7 @@ vid_update_display_offset(t1kvid_t *vid, uint8_t reg)
vid->hsync_offset = ((int)vid->baseline_hsyncpos - (int)vid->crtc[2]) * hsync_scale;
break;
case 7:
if (vid->crtc[7] < vid->crtc[6])
vid->crtc[7] = vid->crtc[6];
else if (vid->crtc[7] > vid->crtc[4])
vid->crtc[7] = vid->crtc[4];
vid->vsync_offset = ((int)vid->baseline_vsyncpos - (int)vid->crtc[7]) * vsync_scale;
vid->vsync_offset_pending = ((int)vid->baseline_vsyncpos - (int)vid->crtc[7]) * vsync_scale;
break;
}
}
@@ -643,8 +639,8 @@ vid_poll(void *priv)
int scanline_old;
int old_ma;
int hos_offs = 8 + vid->hsync_offset;
int displine_offs = vid->displine - vid->vsync_offset;
int displine_offs_double = (vid->displine << 1) - (vid->vsync_offset << 1);
int displine_offs = (vid->displine + vid->vsync_offset < 0) ? 0 : vid->displine + vid->vsync_offset;
int displine_offs_double = displine_offs << 1;
if (!vid->linepos) {
timer_advance_u64(&vid->timer, vid->dispofftime);
@@ -661,51 +657,39 @@ vid_poll(void *priv)
vid->lastline = vid->displine;
switch (vid->double_type) {
default:
if (displine_offs_double >= 0) {
vid_render(dev, displine_offs_double, hos_offs);
vid_render_blank(dev, displine_offs_double + 1);
}
vid_render(dev, displine_offs_double, hos_offs);
vid_render_blank(dev, displine_offs_double + 1);
break;
case DOUBLE_NONE:
if (displine_offs >= 0)
vid_render(dev, displine_offs, hos_offs);
vid_render(dev, displine_offs, hos_offs);
break;
case DOUBLE_SIMPLE:
if (displine_offs_double >= 0) {
old_ma = vid->memaddr;
vid_render(dev, displine_offs_double, hos_offs);
vid->memaddr = old_ma;
vid_render(dev, displine_offs_double + 1, hos_offs);
}
old_ma = vid->memaddr;
vid_render(dev, displine_offs_double, hos_offs);
vid->memaddr = old_ma;
vid_render(dev, displine_offs_double + 1, hos_offs);
break;
}
} else switch (vid->double_type) {
default:
if (displine_offs_double >= 0)
vid_render_blank(dev, displine_offs_double);
vid_render_blank(dev, displine_offs_double);
break;
case DOUBLE_NONE:
if (displine_offs >= 0)
vid_render_blank(dev, displine_offs);
vid_render_blank(dev, displine_offs);
break;
case DOUBLE_SIMPLE:
if (displine_offs_double >= 0) {
vid_render_blank(dev, displine_offs_double);
vid_render_blank(dev, displine_offs_double + 1);
}
vid_render_blank(dev, displine_offs_double);
vid_render_blank(dev, displine_offs_double + 1);
break;
}
switch (vid->double_type) {
default:
if (displine_offs_double >= 0) {
vid_render_process(dev, displine_offs_double);
vid_render_process(dev, displine_offs_double + 1);
}
vid_render_process(dev, displine_offs_double);
vid_render_process(dev, displine_offs_double + 1);
break;
case DOUBLE_NONE:
if (displine_offs >= 0)
vid_render_process(dev, displine_offs);
vid_render_process(dev, displine_offs);
break;
}
@@ -768,7 +752,8 @@ vid_poll(void *priv)
else
vid->cursoron = vid->blink & 16;
}
if (vid->vc == vid->baseline_vsyncpos) {
if (vid->vc == vid->crtc[7]) {
vid->vsync_offset = vid->vsync_offset_pending;
vid->dispon = 0;
vid->displine = 0;
vid->vsynctime = 16;
@@ -875,6 +860,7 @@ tandy_vid_init(tandy_t *dev)
vid->baseline_ready = false;
vid->hsync_offset = 0;
vid->vsync_offset = 0;
vid->vsync_offset_pending = 0;
vid->memctrl = -1;
video_inform(VIDEO_FLAG_TYPE_CGA, &timing_dram);