DREAMWEB: frameoutv becomes a native function

devtools/tasmrecover/tasm-recover

@@ -22,6 +22,7 @@ generator = cpp(context, "DreamGen", blacklist = [
 	'width160',
 	'convertkey',
 	'readabyte',
-	'readoneblock'
+	'readoneblock',
+	'frameoutv'
 	])
 generator.generate('dreamweb') #start routine

engines/dreamweb/dreamgen.cpp

@@ -4329,52 +4329,6 @@ noeffects:
 	cx = pop();
 }
 
-void DreamGenContext::frameoutv() {
-	STACK_CHECK;
-	push(dx);
-	ax = bx;
-	bx = dx;
-	_mul(bx);
-	_add(di, ax);
-	dx = pop();
-	push(cx);
-	ch = 0;
-	_sub(dx, cx);
-	cx = pop();
-frameloop1:
-	push(cx);
-	ch = 0;
-frameloop2:
-	_lodsb();
-	_cmp(al, 0);
-	if (!flags.z())
-		goto backtosolid;
-backtoother:
-	_inc(di);
-	if (--cx)
-		goto frameloop2;
-	cx = pop();
-	_add(di, dx);
-	_dec(ch);
-	if (!flags.z())
-		goto frameloop1;
-	return;
-frameloop3:
-	_lodsb();
-	_cmp(al, 0);
-	if (flags.z())
-		goto backtoother;
-backtosolid:
-	_stosb();
-	if (--cx)
-		goto frameloop3;
-	cx = pop();
-	_add(di, dx);
-	_dec(ch);
-	if (!flags.z())
-		goto frameloop1;
-}
-
 void DreamGenContext::frameoutbh() {
 	STACK_CHECK;
 	push(dx);
@@ -22126,7 +22080,6 @@ void DreamGenContext::__dispatch_call(uint16 addr) {
 		case 0xc214: delthisone(); break;
 		case 0xc228: doblocks(); break;
 		case 0xc22c: showframe(); break;
-		case 0xc230: frameoutv(); break;
 		case 0xc238: frameoutbh(); break;
 		case 0xc23c: frameoutfx(); break;
 		case 0xc240: transferinv(); break;

engines/dreamweb/stubs.cpp

@@ -503,4 +503,26 @@ void DreamGenContext::showpcx() {
 	pcxFile.close();
 }
 
+void DreamGenContext::frameoutv() {
+	uint16 pitch = dx;
+	uint16 width = cx & 0xff;
+	uint16 height = cx >> 8;
+	uint16 stride = pitch - width;
+
+	const uint8* src = ds.ptr(si, width * height);
+	uint8* base = es.ptr(di, stride * height);
+	uint8* dst = base + pitch * bx;
+
+	// NB: Original code assumes non-zero width and height, "for" are unneeded, do-while would suffice but would be less readable
+	for (uint16 y = 0; y < height; ++y) {
+		for (uint16 x = 0; x < width; ++x) {
+			uint8 pixel = *src++;
+			if (pixel)
+				*dst = pixel;
+			++dst;
+		}
+		dst += stride;
+	}
+}
+
 } /*namespace dreamgen */