1 files changed, 454 insertions, 0 deletions
diff --git a/src/libui_sdl/libui/darwin/draw.m b/src/libui_sdl/libui/darwin/draw.m
new file mode 100644
index 0000000..262ad3e
--- /dev/null
+++ b/src/libui_sdl/libui/darwin/draw.m
@@ -0,0 +1,454 @@
+// 6 september 2015
+#import "uipriv_darwin.h"
+
+struct uiDrawPath {
+	CGMutablePathRef path;
+	uiDrawFillMode fillMode;
+	BOOL ended;
+};
+
+uiDrawPath *uiDrawNewPath(uiDrawFillMode mode)
+{
+	uiDrawPath *p;
+
+	p = uiNew(uiDrawPath);
+	p->path = CGPathCreateMutable();
+	p->fillMode = mode;
+	return p;
+}
+
+void uiDrawFreePath(uiDrawPath *p)
+{
+	CGPathRelease((CGPathRef) (p->path));
+	uiFree(p);
+}
+
+void uiDrawPathNewFigure(uiDrawPath *p, double x, double y)
+{
+	if (p->ended)
+		userbug("You cannot call uiDrawPathNewFigure() on a uiDrawPath that has already been ended. (path; %p)", p);
+	CGPathMoveToPoint(p->path, NULL, x, y);
+}
+
+void uiDrawPathNewFigureWithArc(uiDrawPath *p, double xCenter, double yCenter, double radius, double startAngle, double sweep, int negative)
+{
+	double sinStart, cosStart;
+	double startx, starty;
+
+	if (p->ended)
+		userbug("You cannot call uiDrawPathNewFigureWithArc() on a uiDrawPath that has already been ended. (path; %p)", p);
+	sinStart = sin(startAngle);
+	cosStart = cos(startAngle);
+	startx = xCenter + radius * cosStart;
+	starty = yCenter + radius * sinStart;
+	CGPathMoveToPoint(p->path, NULL, startx, starty);
+	uiDrawPathArcTo(p, xCenter, yCenter, radius, startAngle, sweep, negative);
+}
+
+void uiDrawPathLineTo(uiDrawPath *p, double x, double y)
+{
+	// TODO refine this to require being in a path
+	if (p->ended)
+		implbug("attempt to add line to ended path in uiDrawPathLineTo()");
+	CGPathAddLineToPoint(p->path, NULL, x, y);
+}
+
+void uiDrawPathArcTo(uiDrawPath *p, double xCenter, double yCenter, double radius, double startAngle, double sweep, int negative)
+{
+	bool cw;
+
+	// TODO likewise
+	if (p->ended)
+		implbug("attempt to add arc to ended path in uiDrawPathArcTo()");
+	if (sweep > 2 * uiPi)
+		sweep = 2 * uiPi;
+	cw = false;
+	if (negative)
+		cw = true;
+	CGPathAddArc(p->path, NULL,
+		xCenter, yCenter,
+		radius,
+		startAngle, startAngle + sweep,
+		cw);
+}
+
+void uiDrawPathBezierTo(uiDrawPath *p, double c1x, double c1y, double c2x, double c2y, double endX, double endY)
+{
+	// TODO likewise
+	if (p->ended)
+		implbug("attempt to add bezier to ended path in uiDrawPathBezierTo()");
+	CGPathAddCurveToPoint(p->path, NULL,
+		c1x, c1y,
+		c2x, c2y,
+		endX, endY);
+}
+
+void uiDrawPathCloseFigure(uiDrawPath *p)
+{
+	// TODO likewise
+	if (p->ended)
+		implbug("attempt to close figure of ended path in uiDrawPathCloseFigure()");
+	CGPathCloseSubpath(p->path);
+}
+
+void uiDrawPathAddRectangle(uiDrawPath *p, double x, double y, double width, double height)
+{
+	if (p->ended)
+		userbug("You cannot call uiDrawPathAddRectangle() on a uiDrawPath that has already been ended. (path; %p)", p);
+	CGPathAddRect(p->path, NULL, CGRectMake(x, y, width, height));
+}
+
+void uiDrawPathEnd(uiDrawPath *p)
+{
+	p->ended = TRUE;
+}
+
+struct uiDrawContext {
+	CGContextRef c;
+	CGFloat height;				// needed for text; see below
+};
+
+uiDrawContext *newContext(CGContextRef ctxt, CGFloat height)
+{
+	uiDrawContext *c;
+
+	c = uiNew(uiDrawContext);
+	c->c = ctxt;
+	c->height = height;
+	return c;
+}
+
+void freeContext(uiDrawContext *c)
+{
+	uiFree(c);
+}
+
+// a stroke is identical to a fill of a stroked path
+// we need to do this in order to stroke with a gradient; see http://stackoverflow.com/a/25034854/3408572
+// doing this for other brushes works too
+void uiDrawStroke(uiDrawContext *c, uiDrawPath *path, uiDrawBrush *b, uiDrawStrokeParams *p)
+{
+	CGLineCap cap;
+	CGLineJoin join;
+	CGPathRef dashPath;
+	CGFloat *dashes;
+	size_t i;
+	uiDrawPath p2;
+
+	if (!path->ended)
+		userbug("You cannot call uiDrawStroke() on a uiDrawPath that has not been ended. (path: %p)", path);
+
+	switch (p->Cap) {
+	case uiDrawLineCapFlat:
+		cap = kCGLineCapButt;
+		break;
+	case uiDrawLineCapRound:
+		cap = kCGLineCapRound;
+		break;
+	case uiDrawLineCapSquare:
+		cap = kCGLineCapSquare;
+		break;
+	}
+	switch (p->Join) {
+	case uiDrawLineJoinMiter:
+		join = kCGLineJoinMiter;
+		break;
+	case uiDrawLineJoinRound:
+		join = kCGLineJoinRound;
+		break;
+	case uiDrawLineJoinBevel:
+		join = kCGLineJoinBevel;
+		break;
+	}
+
+	// create a temporary path identical to the previous one
+	dashPath = (CGPathRef) path->path;
+	if (p->NumDashes != 0) {
+		dashes = (CGFloat *) uiAlloc(p->NumDashes * sizeof (CGFloat), "CGFloat[]");
+		for (i = 0; i < p->NumDashes; i++)
+			dashes[i] = p->Dashes[i];
+		dashPath = CGPathCreateCopyByDashingPath(path->path,
+			NULL,
+			p->DashPhase,
+			dashes,
+			p->NumDashes);
+		uiFree(dashes);
+	}
+	// the documentation is wrong: this produces a path suitable for calling CGPathCreateCopyByStrokingPath(), not for filling directly
+	// the cast is safe; we never modify the CGPathRef and always cast it back to a CGPathRef anyway
+	p2.path = (CGMutablePathRef) CGPathCreateCopyByStrokingPath(dashPath,
+		NULL,
+		p->Thickness,
+		cap,
+		join,
+		p->MiterLimit);
+	if (p->NumDashes != 0)
+		CGPathRelease(dashPath);
+
+	// always draw stroke fills using the winding rule
+	// otherwise intersecting figures won't draw correctly
+	p2.fillMode = uiDrawFillModeWinding;
+	p2.ended = path->ended;
+	uiDrawFill(c, &p2, b);
+	// and clean up
+	CGPathRelease((CGPathRef) (p2.path));
+}
+
+// for a solid fill, we can merely have Core Graphics fill directly
+static void fillSolid(CGContextRef ctxt, uiDrawPath *p, uiDrawBrush *b)
+{
+	// TODO this uses DeviceRGB; switch to sRGB
+	CGContextSetRGBFillColor(ctxt, b->R, b->G, b->B, b->A);
+	switch (p->fillMode) {
+	case uiDrawFillModeWinding:
+		CGContextFillPath(ctxt);
+		break;
+	case uiDrawFillModeAlternate:
+		CGContextEOFillPath(ctxt);
+		break;
+	}
+}
+
+// for a gradient fill, we need to clip to the path and then draw the gradient
+// see http://stackoverflow.com/a/25034854/3408572
+static void fillGradient(CGContextRef ctxt, uiDrawPath *p, uiDrawBrush *b)
+{
+	CGGradientRef gradient;
+	CGColorSpaceRef colorspace;
+	CGFloat *colors;
+	CGFloat *locations;
+	size_t i;
+
+	// gradients need a color space
+	// for consistency with windows, use sRGB
+	colorspace = CGColorSpaceCreateWithName(kCGColorSpaceSRGB);
+
+	// make the gradient
+	colors = uiAlloc(b->NumStops * 4 * sizeof (CGFloat), "CGFloat[]");
+	locations = uiAlloc(b->NumStops * sizeof (CGFloat), "CGFloat[]");
+	for (i = 0; i < b->NumStops; i++) {
+		colors[i * 4 + 0] = b->Stops[i].R;
+		colors[i * 4 + 1] = b->Stops[i].G;
+		colors[i * 4 + 2] = b->Stops[i].B;
+		colors[i * 4 + 3] = b->Stops[i].A;
+		locations[i] = b->Stops[i].Pos;
+	}
+	gradient = CGGradientCreateWithColorComponents(colorspace, colors, locations, b->NumStops);
+	uiFree(locations);
+	uiFree(colors);
+
+	// because we're mucking with clipping, we need to save the graphics state and restore it later
+	CGContextSaveGState(ctxt);
+
+	// clip
+	switch (p->fillMode) {
+	case uiDrawFillModeWinding:
+		CGContextClip(ctxt);
+		break;
+	case uiDrawFillModeAlternate:
+		CGContextEOClip(ctxt);
+		break;
+	}
+
+	// draw the gradient
+	switch (b->Type) {
+	case uiDrawBrushTypeLinearGradient:
+		CGContextDrawLinearGradient(ctxt,
+			gradient,
+			CGPointMake(b->X0, b->Y0),
+			CGPointMake(b->X1, b->Y1),
+			kCGGradientDrawsBeforeStartLocation | kCGGradientDrawsAfterEndLocation);
+		break;
+	case uiDrawBrushTypeRadialGradient:
+		CGContextDrawRadialGradient(ctxt,
+			gradient,
+			CGPointMake(b->X0, b->Y0),
+			// make the start circle radius 0 to make it a point
+			0,
+			CGPointMake(b->X1, b->Y1),
+			b->OuterRadius,
+			kCGGradientDrawsBeforeStartLocation | kCGGradientDrawsAfterEndLocation);
+		break;
+	}
+
+	// and clean up
+	CGContextRestoreGState(ctxt);
+	CGGradientRelease(gradient);
+	CGColorSpaceRelease(colorspace);
+}
+
+void uiDrawFill(uiDrawContext *c, uiDrawPath *path, uiDrawBrush *b)
+{
+	if (!path->ended)
+		userbug("You cannot call uiDrawStroke() on a uiDrawPath that has not been ended. (path: %p)", path);
+	CGContextAddPath(c->c, (CGPathRef) (path->path));
+	switch (b->Type) {
+	case uiDrawBrushTypeSolid:
+		fillSolid(c->c, path, b);
+		return;
+	case uiDrawBrushTypeLinearGradient:
+	case uiDrawBrushTypeRadialGradient:
+		fillGradient(c->c, path, b);
+		return;
+//	case uiDrawBrushTypeImage:
+		// TODO
+		return;
+	}
+	userbug("Unknown brush type %d passed to uiDrawFill().", b->Type);
+}
+
+static void m2c(uiDrawMatrix *m, CGAffineTransform *c)
+{
+	c->a = m->M11;
+	c->b = m->M12;
+	c->c = m->M21;
+	c->d = m->M22;
+	c->tx = m->M31;
+	c->ty = m->M32;
+}
+
+static void c2m(CGAffineTransform *c, uiDrawMatrix *m)
+{
+	m->M11 = c->a;
+	m->M12 = c->b;
+	m->M21 = c->c;
+	m->M22 = c->d;
+	m->M31 = c->tx;
+	m->M32 = c->ty;
+}
+
+void uiDrawMatrixTranslate(uiDrawMatrix *m, double x, double y)
+{
+	CGAffineTransform c;
+
+	m2c(m, &c);
+	c = CGAffineTransformTranslate(c, x, y);
+	c2m(&c, m);
+}
+
+void uiDrawMatrixScale(uiDrawMatrix *m, double xCenter, double yCenter, double x, double y)
+{
+	CGAffineTransform c;
+	double xt, yt;
+
+	m2c(m, &c);
+	xt = x;
+	yt = y;
+	scaleCenter(xCenter, yCenter, &xt, &yt);
+	c = CGAffineTransformTranslate(c, xt, yt);
+	c = CGAffineTransformScale(c, x, y);
+	c = CGAffineTransformTranslate(c, -xt, -yt);
+	c2m(&c, m);
+}
+
+void uiDrawMatrixRotate(uiDrawMatrix *m, double x, double y, double amount)
+{
+	CGAffineTransform c;
+
+	m2c(m, &c);
+	c = CGAffineTransformTranslate(c, x, y);
+	c = CGAffineTransformRotate(c, amount);
+	c = CGAffineTransformTranslate(c, -x, -y);
+	c2m(&c, m);
+}
+
+void uiDrawMatrixSkew(uiDrawMatrix *m, double x, double y, double xamount, double yamount)
+{
+	fallbackSkew(m, x, y, xamount, yamount);
+}
+
+void uiDrawMatrixMultiply(uiDrawMatrix *dest, uiDrawMatrix *src)
+{
+	CGAffineTransform c;
+	CGAffineTransform d;
+
+	m2c(dest, &c);
+	m2c(src, &d);
+	c = CGAffineTransformConcat(c, d);
+	c2m(&c, dest);
+}
+
+// there is no test for invertibility; CGAffineTransformInvert() is merely documented as returning the matrix unchanged if it isn't invertible
+// therefore, special care must be taken to catch matrices who are their own inverses
+// TODO figure out which matrices these are and do so
+int uiDrawMatrixInvertible(uiDrawMatrix *m)
+{
+	CGAffineTransform c, d;
+
+	m2c(m, &c);
+	d = CGAffineTransformInvert(c);
+	return CGAffineTransformEqualToTransform(c, d) == false;
+}
+
+int uiDrawMatrixInvert(uiDrawMatrix *m)
+{
+	CGAffineTransform c, d;
+
+	m2c(m, &c);
+	d = CGAffineTransformInvert(c);
+	if (CGAffineTransformEqualToTransform(c, d))
+		return 0;
+	c2m(&d, m);
+	return 1;
+}
+
+void uiDrawMatrixTransformPoint(uiDrawMatrix *m, double *x, double *y)
+{
+	CGAffineTransform c;
+	CGPoint p;
+
+	m2c(m, &c);
+	p = CGPointApplyAffineTransform(CGPointMake(*x, *y), c);
+	*x = p.x;
+	*y = p.y;
+}
+
+void uiDrawMatrixTransformSize(uiDrawMatrix *m, double *x, double *y)
+{
+	CGAffineTransform c;
+	CGSize s;
+
+	m2c(m, &c);
+	s = CGSizeApplyAffineTransform(CGSizeMake(*x, *y), c);
+	*x = s.width;
+	*y = s.height;
+}
+
+void uiDrawTransform(uiDrawContext *c, uiDrawMatrix *m)
+{
+	CGAffineTransform cm;
+
+	m2c(m, &cm);
+	CGContextConcatCTM(c->c, cm);
+}
+
+void uiDrawClip(uiDrawContext *c, uiDrawPath *path)
+{
+	if (!path->ended)
+		userbug("You cannot call uiDrawCilp() on a uiDrawPath that has not been ended. (path: %p)", path);
+	CGContextAddPath(c->c, (CGPathRef) (path->path));
+	switch (path->fillMode) {
+	case uiDrawFillModeWinding:
+		CGContextClip(c->c);
+		break;
+	case uiDrawFillModeAlternate:
+		CGContextEOClip(c->c);
+		break;
+	}
+}
+
+// TODO figure out what besides transforms these save/restore on all platforms
+void uiDrawSave(uiDrawContext *c)
+{
+	CGContextSaveGState(c->c);
+}
+
+void uiDrawRestore(uiDrawContext *c)
+{
+	CGContextRestoreGState(c->c);
+}
+
+void uiDrawText(uiDrawContext *c, double x, double y, uiDrawTextLayout *layout)
+{
+	doDrawText(c->c, c->height, x, y, layout);
+}