From: Toni Wilen <twilen@winuae.net>
Date: Sun, 8 Mar 2026 18:40:44 +0000 (+0200)
Subject: Screen mode aspect ratio auto detection updates
X-Git-Url: https://git.unchartedbackwaters.co.uk/w/?a=commitdiff_plain;h=1722a382062b61d5f3bd7345601916c691f3f6bb;p=francis%2Fwinuae.git

Screen mode aspect ratio auto detection updates
---

diff --git a/custom.cpp b/custom.cpp
index b5d474b0..883c00d1 100644
--- a/custom.cpp
+++ b/custom.cpp
@@ -619,7 +619,7 @@ float hblank_hz;
 static float vblank_hz_lof, vblank_hz_shf, vblank_hz_lace;
 static int vblank_hz_mult, vblank_hz_state;
 static struct chipset_refresh *stored_chipset_refresh;
-int doublescan;
+int doublescan, doublescan2x;
 int programmedmode;
 frame_time_t syncbase;
 static int fmode_saved, fmode, fmode_inuse;
@@ -1775,6 +1775,23 @@ void compute_framesync(void)
 	resetfulllinestate();
 }
 
+static bool line_is_doubled(void)
+{
+	if (doflickerfix_active()) {
+		return true;
+	}
+	if (!interlace_seen && doublescan <= 0 && currprefs.gfx_vresolution && currprefs.gfx_pscanlines > 1) {
+		return true;
+	}
+	if ((doublescan <= 0 || interlace_seen > 0) && currprefs.gfx_vresolution && currprefs.gfx_iscanlines) {
+		return true;
+	}
+	if (currprefs.gfx_vresolution && (doublescan <= 0 || interlace_seen > 0)) {
+		return true;
+	}
+	return false;
+}
+
 /* set PAL/NTSC or custom timing variables */
 static void init_beamcon0(void)
 {
@@ -1785,6 +1802,7 @@ static void init_beamcon0(void)
 	beamcon0 = new_beamcon0;
 
 	doublescan = 0;
+	doublescan2x = 0;
 	programmedmode = 0;
 	lines_after_beamcon_change = 5;
 
@@ -2191,13 +2209,30 @@ static void init_beamcon0(void)
 		maxvpos_display = vsync_lines;
 
 		programmedmode = 2;
-		if ((hsync_ccks < 226 || hsync_ccks > 229) || (vsync_lines < 256 || vsync_lines > 320)) {
-			doublescan = hsync_ccks <= 164 && vsync_lines >= 350 ? 1 : 0;
-			// if superhires and wide enough: not doublescan
-			if (doublescan && hsync_ccks >= 140 && (bplcon0 & 0x0040))
-				doublescan = 0;
+	}
+
+	int hpixels = maxhpos_display * 2;
+	int vpixels = vsync_lines - minfirstline;
+	int hpixelsd = hpixels * 80 / 100;
+	if (hpixelsd < vpixels) {
+		doublescan = 1;
+		if (programmedmode == 2) {
 			programmedmode = 1;
 		}
+		hpixelsd *= 2;
+	}
+	bool dbl = line_is_doubled();
+	if (dbl) {
+		vpixels *= 2;
+	}
+	if (hpixelsd < vpixels) {
+		doublescan2x = 1;
+		hpixelsd *= 2;
+		if (hpixelsd < vpixels) {
+			doublescan2x = 2;
+		}
+	} else if (hpixelsd > vpixels * 2) {
+		doublescan2x = -1;
 	}
 
 	if (maxvpos_nom >= MAXVPOS) {
diff --git a/drawing.cpp b/drawing.cpp
index 49626d8c..9617632c 100644
--- a/drawing.cpp
+++ b/drawing.cpp
@@ -407,6 +407,7 @@ static bool ecs_genlock_features_active;
 static uae_u8 ecs_genlock_features_mask;
 static bool ecs_genlock_features_colorkey;
 static bool aga_genlock_features_zdclken;
+static int doublescan2xx;
 
 uae_sem_t gui_sem;
 
@@ -1393,8 +1394,9 @@ static void center_image(void)
 		visible_left_border = maxdiw - w;
 		visible_left_border &= ~((xshift(1, 0)) - 1);
 
+		int hresdb = hresolution_inv + (doublescan == 1 ? 1 : 0);
 		int ww = (diwlastword_total - diwfirstword_total) >> hresolution_inv;
-		int wx = ((diwfirstword_total) >> hresolution_inv) - (((hdisplay_left_border - 1) * 4) >> (hresolution_inv + (doublescan == 1 ? 1 : 0)));
+		int wx = ((diwfirstword_total) >> hresdb) - (((hdisplay_left_border - 1) * 4) >> hresdb);
 
 		if (ww < w && currprefs.gfx_xcenter == 2) {
 			/* Try to center. */
@@ -3233,9 +3235,24 @@ static void expand_bplcon1(uae_u16 v)
 	check_lts_request();
 }
 
+int getvresolution(void)
+{
+	int v = currprefs.gfx_vresolution;
+	if (v < 0) {
+		return 0;
+	}
+	return v;
+}
+
 int gethresolution(void)
 {
-	int h = currprefs.gfx_resolution;
+	int h = currprefs.gfx_resolution - doublescan2x - doublescan2xx;
+	if (h < 0) {
+		h = 0;
+	}
+	if (h > RES_MAX2X) { 
+		h = RES_MAX2X;
+	}
 	if (autoswitch_old_resolution == RES_HIRES && currprefs.gfx_resolution == RES_SUPERHIRES) {
 		h--;
 	}
@@ -3245,10 +3262,12 @@ int gethresolution(void)
 static void sethresolution(void)
 {
 	hresolution = currprefs.gfx_resolution;
+	doublescan2xx = 0;
 	if (doublescan == 1) {
 		hresolution++;
 		if (hresolution > RES_SUPERHIRES) {
 			hresolution = RES_SUPERHIRES;
+			doublescan2xx = 1;
 		}
 	}
 	hresolution_inv = RES_MAX - hresolution;
diff --git a/include/custom.h b/include/custom.h
index 19f7018b..5bafd4fa 100644
--- a/include/custom.h
+++ b/include/custom.h
@@ -143,7 +143,7 @@ extern int hsyncstartpos_hw, hsyncendpos_hw;
 extern int minfirstline, minfirstline_linear, vblank_endline, numscrlines, minfirstline_linear;
 extern float vblank_hz, fake_vblank_hz;
 extern float hblank_hz;
-extern int vblank_skip, doublescan;
+extern int vblank_skip, doublescan, doublescan2x;
 extern int programmedmode;
 extern int display_reset;
 
@@ -190,6 +190,7 @@ extern int xbluecolor_s, xbluecolor_b, xbluecolor_m;
 #define RES_HIRES 1
 #define RES_SUPERHIRES 2
 #define RES_MAX 2
+#define RES_MAX2X 3
 #define VRES_NONDOUBLE 0
 #define VRES_DOUBLE 1
 #define VRES_QUAD 2
diff --git a/include/drawing.h b/include/drawing.h
index a9c9b2f3..16c34420 100644
--- a/include/drawing.h
+++ b/include/drawing.h
@@ -197,6 +197,7 @@ void denise_handle_quick_strobe_queue(uae_u16 strobe, int strobe_pos, int endpos
 bool drawing_can_lineoptimizations(void);
 void set_drawbuffer(void);
 int gethresolution(void);
+int getvresolution(void);
 void denise_update_reg_queue(uae_u16 reg, uae_u16 v, uae_u32 linecnt);
 void denise_store_restore_registers_queue(bool store, uae_u32 linecnt);
 void denise_clearbuffers(void);
diff --git a/od-win32/win32_scaler.cpp b/od-win32/win32_scaler.cpp
index c97636d5..abb79070 100644
--- a/od-win32/win32_scaler.cpp
+++ b/od-win32/win32_scaler.cpp
@@ -65,7 +65,7 @@ static bool getmanualpos(int monid, int *cxp, int *cyp, int *cwp, int *chp)
 			}
 		}
 #endif
-		cw = avidinfo->outbuffer->outwidth << 1;
+		cw = avidinfo->outbuffer->outwidth << (RES_MAX - currprefs.gfx_resolution);
 	} else {	
 		cw = v;
 	}
@@ -83,7 +83,7 @@ static bool getmanualpos(int monid, int *cxp, int *cyp, int *cwp, int *chp)
 			ch = native ? (current_linear_vpos - minfirstline) << VRES_MAX : avidinfo->outbuffer->outheight;
 		}
 #endif
-		ch = avidinfo->outbuffer->outheight;
+		ch = avidinfo->outbuffer->outheight << (VRES_MAX - currprefs.gfx_vresolution);
 	} else {
 		ch = v;
 	}
@@ -284,10 +284,11 @@ void getfilterdata(int monid, struct displayscale *ds)
 		filter_aspect = 0;
 		keep_aspect = 0;
 		if (ds->dstwidth >= 640 && ds->dstwidth <= 800 && ds->dstheight >= 480 && ds->dstheight <= 600) {
+			int hres = currprefs.gfx_resolution + doublescan2x;
 			autoselect = 1;
 			scalemode = AUTOSCALE_NONE;
 			int m = 1;
-			int w = AMIGA_WIDTH_MAX << currprefs.gfx_resolution;
+			int w = AMIGA_WIDTH_MAX << hres;
 			int h = AMIGA_HEIGHT_MAX << currprefs.gfx_vresolution;
 			for (;;) {
 				if (w * (m * 2) > ds->dstwidth || h * (m * 2) > ds->dstheight) {
@@ -321,7 +322,7 @@ void getfilterdata(int monid, struct displayscale *ds)
 	if (scalemode) {
 		int cw, ch, cx, cy, cv = 0, crealh = 0;
 		int hres = gethresolution();
-		int vres = currprefs.gfx_vresolution;
+		int vres = getvresolution();
 		static int oxmult, oymult;
 
 		filterxmult = (float)ds->scale;
@@ -526,16 +527,23 @@ void getfilterdata(int monid, struct displayscale *ds)
 
 			if (scalemode == AUTOSCALE_CENTER) {
 
-				int scalex = ds->scale;
-				int scaley = ds->scale;
+				float scalex = ds->scale;
+				float scaley = ds->scale;
+				float scale2x = 1.0;
+				float scale2y = 1.0;
+				if (doublescan2x > 0) {
+					scale2x = 0.5 / doublescan2x;
+				} else if (doublescan2x < 0) {
+					scale2y = 0.5 / (-doublescan2x);
+				}
 
 				int ww = cw * scalex;
 				int hh = ch * scaley;
 
-				ds->outwidth = ds->dstwidth * ds->scale;
-				ds->outheight = ds->dstheight * ds->scale;
-				ds->xoffset += cx * ds->scale - (ds->dstwidth - ww) / 2;
-				ds->yoffset += cy * ds->scale - (ds->dstheight - hh) / 2;
+				ds->outwidth = ds->dstwidth * scalex * scale2x;
+				ds->outheight = ds->dstheight * scaley * scale2y;
+				ds->xoffset += cx * scalex - (ds->outwidth - ww) / 2;
+				ds->yoffset += cy * scaley - (ds->outheight - hh) / 2;
 
 				goto cont;
 
@@ -586,6 +594,12 @@ void getfilterdata(int monid, struct displayscale *ds)
 				float palntscratio = getpalntscratio(dstratio, keep_aspect, palntscadjust);
 				scaley = scaley * palntscratio / dstratio;
 
+				if (doublescan2x > 0) {
+					scalex *= 2.0 * doublescan2x;
+				} else if (doublescan2x < 0) {
+					scaley *= 2.0 * (-doublescan2x);
+				}
+
 				ds->outwidth = (int)(cw * ds->scale);
 				ds->outheight = (int)(ch * ds->scale);
 				ds->xoffset += cx * ds->scale;
@@ -674,10 +688,18 @@ void getfilterdata(int monid, struct displayscale *ds)
 		int ch = avidinfo->drawbuffer.inheight;
 		set_custom_limits(cw, ch, 0, 0, true);
 
-		ds->outwidth = ds->dstwidth;
-		ds->outheight = ds->dstheight;
-		ds->xoffset = (ds->srcwidth - ds->dstwidth) / 2;
-		ds->yoffset = (ds->srcheight - ds->dstheight) / 2;
+		int dw = ds->dstwidth;
+		int dh = ds->dstheight;
+		if (doublescan2x > 0) {
+			dw >>= doublescan2x;
+		} else if (doublescan2x < 0) {
+			dh >>= -doublescan2x;
+		}
+
+		ds->outwidth = dw;
+		ds->outheight = dh;
+		ds->xoffset = (ds->srcwidth - dw) / 2;
+		ds->yoffset = (ds->srcheight - dh) / 2;
 
 	}
 cont: