Wrote much of the new text layout code on Windows. Now to test.

windows/_old_drawtext.cpp

@@ -77,152 +77,8 @@ uiDrawTextFont *mkTextFont(IDWriteFont *df, BOOL addRef, WCHAR *family, BOOL cop
 	return font;
 }
 
-// TODO consider moving these all to dwrite.cpp
-
 // TODO MinGW-w64 is missing this one
 #define DWRITE_FONT_WEIGHT_SEMI_LIGHT (DWRITE_FONT_WEIGHT(350))
-static const struct {
-	bool lastOne;
-	uiDrawTextWeight uival;
-	DWRITE_FONT_WEIGHT dwval;
-} dwriteWeights[] = {
-	{ false, uiDrawTextWeightThin, DWRITE_FONT_WEIGHT_THIN },
-	{ false, uiDrawTextWeightUltraLight, DWRITE_FONT_WEIGHT_ULTRA_LIGHT },
-	{ false, uiDrawTextWeightLight, DWRITE_FONT_WEIGHT_LIGHT },
-	{ false, uiDrawTextWeightBook, DWRITE_FONT_WEIGHT_SEMI_LIGHT },
-	{ false, uiDrawTextWeightNormal, DWRITE_FONT_WEIGHT_NORMAL },
-	{ false, uiDrawTextWeightMedium, DWRITE_FONT_WEIGHT_MEDIUM },
-	{ false, uiDrawTextWeightSemiBold, DWRITE_FONT_WEIGHT_SEMI_BOLD },
-	{ false, uiDrawTextWeightBold, DWRITE_FONT_WEIGHT_BOLD },
-	{ false, uiDrawTextWeightUltraBold, DWRITE_FONT_WEIGHT_ULTRA_BOLD },
-	{ false, uiDrawTextWeightHeavy, DWRITE_FONT_WEIGHT_HEAVY },
-	{ true, uiDrawTextWeightUltraHeavy, DWRITE_FONT_WEIGHT_ULTRA_BLACK, },
-};
-
-static const struct {
-	bool lastOne;
-	uiDrawTextItalic uival;
-	DWRITE_FONT_STYLE dwval;
-} dwriteItalics[] = {
-	{ false, uiDrawTextItalicNormal, DWRITE_FONT_STYLE_NORMAL },
-	{ false, uiDrawTextItalicOblique, DWRITE_FONT_STYLE_OBLIQUE },
-	{ true, uiDrawTextItalicItalic, DWRITE_FONT_STYLE_ITALIC },
-};
-
-static const struct {
-	bool lastOne;
-	uiDrawTextStretch uival;
-	DWRITE_FONT_STRETCH dwval;
-} dwriteStretches[] = {
-	{ false, uiDrawTextStretchUltraCondensed, DWRITE_FONT_STRETCH_ULTRA_CONDENSED },
-	{ false, uiDrawTextStretchExtraCondensed, DWRITE_FONT_STRETCH_EXTRA_CONDENSED },
-	{ false, uiDrawTextStretchCondensed, DWRITE_FONT_STRETCH_CONDENSED },
-	{ false, uiDrawTextStretchSemiCondensed, DWRITE_FONT_STRETCH_SEMI_CONDENSED },
-	{ false, uiDrawTextStretchNormal, DWRITE_FONT_STRETCH_NORMAL },
-	{ false, uiDrawTextStretchSemiExpanded, DWRITE_FONT_STRETCH_SEMI_EXPANDED },
-	{ false, uiDrawTextStretchExpanded, DWRITE_FONT_STRETCH_EXPANDED },
-	{ false, uiDrawTextStretchExtraExpanded, DWRITE_FONT_STRETCH_EXTRA_EXPANDED },
-	{ true, uiDrawTextStretchUltraExpanded, DWRITE_FONT_STRETCH_ULTRA_EXPANDED },
-};
-
-void attrToDWriteAttr(struct dwriteAttr *attr)
-{
-	bool found;
-	int i;
-
-	found = false;
-	for (i = 0; ; i++) {
-		if (dwriteWeights[i].uival == attr->weight) {
-			attr->dweight = dwriteWeights[i].dwval;
-			found = true;
-			break;
-		}
-		if (dwriteWeights[i].lastOne)
-			break;
-	}
-	if (!found)
-		userbug("Invalid text weight %d passed to text function.", attr->weight);
-
-	found = false;
-	for (i = 0; ; i++) {
-		if (dwriteItalics[i].uival == attr->italic) {
-			attr->ditalic = dwriteItalics[i].dwval;
-			found = true;
-			break;
-		}
-		if (dwriteItalics[i].lastOne)
-			break;
-	}
-	if (!found)
-		userbug("Invalid text italic %d passed to text function.", attr->italic);
-
-	found = false;
-	for (i = 0; ; i++) {
-		if (dwriteStretches[i].uival == attr->stretch) {
-			attr->dstretch = dwriteStretches[i].dwval;
-			found = true;
-			break;
-		}
-		if (dwriteStretches[i].lastOne)
-			break;
-	}
-	if (!found)
-		// TODO on other platforms too
-		userbug("Invalid text stretch %d passed to text function.", attr->stretch);
-}
-
-void dwriteAttrToAttr(struct dwriteAttr *attr)
-{
-	int weight, against, n;
-	int curdiff, curindex;
-	bool found;
-	int i;
-
-	// weight is scaled; we need to test to see what's nearest
-	weight = (int) (attr->dweight);
-	against = (int) (dwriteWeights[0].dwval);
-	curdiff = abs(against - weight);
-	curindex = 0;
-	for (i = 1; ; i++) {
-		against = (int) (dwriteWeights[i].dwval);
-		n = abs(against - weight);
-		if (n < curdiff) {
-			curdiff = n;
-			curindex = i;
-		}
-		if (dwriteWeights[i].lastOne)
-			break;
-	}
-	attr->weight = dwriteWeights[i].uival;
-
-	// italic and stretch are simple values; we can just do a matching search
-	found = false;
-	for (i = 0; ; i++) {
-		if (dwriteItalics[i].dwval == attr->ditalic) {
-			attr->italic = dwriteItalics[i].uival;
-			found = true;
-			break;
-		}
-		if (dwriteItalics[i].lastOne)
-			break;
-	}
-	if (!found)
-		// these are implbug()s because users shouldn't be able to get here directly; TODO?
-		implbug("invalid italic %d passed to dwriteAttrToAttr()", attr->ditalic);
-
-	found = false;
-	for (i = 0; ; i++) {
-		if (dwriteStretches[i].dwval == attr->dstretch) {
-			attr->stretch = dwriteStretches[i].uival;
-			found = true;
-			break;
-		}
-		if (dwriteStretches[i].lastOne)
-			break;
-	}
-	if (!found)
-		implbug("invalid stretch %d passed to dwriteAttrToAttr()", attr->dstretch);
-}
 
 uiDrawTextFont *uiDrawLoadClosestFont(const uiDrawTextFontDescriptor *desc)
 {
@@ -357,13 +213,7 @@ uiDrawTextLayout *uiDrawNewTextLayout(const char *text, uiDrawTextFont *defaultF
 		defaultFont->f->GetWeight(),
 		defaultFont->f->GetStyle(),
 		defaultFont->f->GetStretch(),
-		// typographic points are 1/72 inch; this parameter is 1/96 inch
+
-		// fortunately Microsoft does this too, in https://msdn.microsoft.com/en-us/library/windows/desktop/dd371554%28v=vs.85%29.aspx
-		defaultFont->size * (96.0 / 72.0),
-		// see http://stackoverflow.com/questions/28397971/idwritefactorycreatetextformat-failing and https://msdn.microsoft.com/en-us/library/windows/desktop/dd368203.aspx
-		// TODO use the current locale again?
-		L"",
-		&(layout->format));
 	if (hr != S_OK)
 		logHRESULT(L"error creating IDWriteTextFormat", hr);
 
@@ -417,18 +267,8 @@ IDWriteTextLayout *prepareLayout(uiDrawTextLayout *layout, ID2D1RenderTarget *rt
 	IDWriteTextLayout *dl;
 	DWRITE_TEXT_RANGE range;
 	IUnknown *unkBrush;
-	DWRITE_WORD_WRAPPING wrap;
-	FLOAT maxWidth;
 	HRESULT hr;
 
-	hr = dwfactory->CreateTextLayout(layout->text, layout->textlen,
-		layout->format,
-		// FLOAT is float, not double, so this should work... TODO
-		FLT_MAX, FLT_MAX,
-		&dl);
-	if (hr != S_OK)
-		logHRESULT(L"error creating IDWriteTextLayout", hr);
-
 	for (const struct layoutAttr &attr : *(layout->attrs)) {
 		range.startPosition = layout->graphemes[attr.start];
 		range.length = layout->graphemes[attr.end] - layout->graphemes[attr.start];
@@ -452,48 +292,12 @@ IDWriteTextLayout *prepareLayout(uiDrawTextLayout *layout, ID2D1RenderTarget *rt
 			logHRESULT(L"error adding attribute to text layout", hr);
 	}
 
-	// and set the width
+
-	// this is the only wrapping mode (apart from "no wrap") available prior to Windows 8.1
-	wrap = DWRITE_WORD_WRAPPING_WRAP;
-	maxWidth = layout->width;
-	if (layout->width < 0) {
-		wrap = DWRITE_WORD_WRAPPING_NO_WRAP;
-		// setting the max width in this case technically isn't needed since the wrap mode will simply ignore the max width, but let's do it just to be safe
-		maxWidth = FLT_MAX;		// see TODO above
-	}
-	hr = dl->SetWordWrapping(wrap);
-	if (hr != S_OK)
-		logHRESULT(L"error setting word wrapping mode", hr);
-	hr = dl->SetMaxWidth(maxWidth);
-	if (hr != S_OK)
-		logHRESULT(L"error setting max layout width", hr);
 
 	return dl;
 }
 
 
-void uiDrawTextLayoutSetWidth(uiDrawTextLayout *layout, double width)
-{
-	layout->width = width;
-}
-
-// TODO for a single line the height includes the leading; it should not
-void uiDrawTextLayoutExtents(uiDrawTextLayout *layout, double *width, double *height)
-{
-	IDWriteTextLayout *dl;
-	DWRITE_TEXT_METRICS metrics;
-	HRESULT hr;
-
-	dl = prepareLayout(layout, NULL);
-	hr = dl->GetMetrics(&metrics);
-	if (hr != S_OK)
-		logHRESULT(L"error getting layout metrics", hr);
-	*width = metrics.width;
-	// TODO make sure the behavior of this on empty strings is the same on all platforms
-	*height = metrics.height;
-	dl->Release();
-}
-
 void uiDrawText(uiDrawContext *c, double x, double y, uiDrawTextLayout *layout)
 {
 	IDWriteTextLayout *dl;

windows/areaevents.cpp

@@ -2,6 +2,8 @@
 #include "uipriv_windows.hpp"
 #include "area.hpp"
 
+// TODO https://github.com/Microsoft/Windows-classic-samples/blob/master/Samples/Win7Samples/multimedia/DirectWrite/PadWrite/TextEditor.cpp notes on explicit RTL handling under MirrorXCoordinate(); also in areadraw.cpp too?
+
 static uiModifiers getModifiers(void)
 {
 	uiModifiers m = 0;

windows/drawtext.cpp

@@ -0,0 +1,244 @@
+// 17 january 2017
+#include "uipriv_windows.hpp"
+
+struct uiDrawTextLayout {
+	IDWriteTextFormat *format;
+	IDWriteTextLayout *layout;
+	UINT32 *nLines;
+	struct lineInfo *lineInfo;
+	// for converting DirectWrite indices to byte offsets
+	size_t *u16tou8;
+	size_t nu16tou8;		// TODO I don't like the casing of this name; is it even necessary?
+};
+
+// typographic points are 1/72 inch; this parameter is 1/96 inch
+// fortunately Microsoft does this too, in https://msdn.microsoft.com/en-us/library/windows/desktop/dd371554%28v=vs.85%29.aspx
+#define pointSizeToDWriteSize(size) (size * (96.0 / 72.0))
+
+static const DWRITE_FONT_STYLE dwriteItalics[] = {
+	[uiDrawTextItalicNormal] = DWRITE_FONT_STYLE_NORMAL,
+	[uiDrawTextItalicOblique] = DWRITE_FONT_STYLE_OBLIQUE,
+	[uiDrawTextItalicItalic] = DWRITE_FONT_STYLE_ITALIC,
+};
+
+static const DWRITE_FONT_STRETCH dwriteStretches[] = {
+	[uiDrawTextStretchUltraCondensed] = DWRITE_FONT_STRETCH_ULTRA_CONDENSED,
+	[uiDrawTextStretchExtraCondensed] = DWRITE_FONT_STRETCH_EXTRA_CONDENSED,
+	[uiDrawTextStretchCondensed] = DWRITE_FONT_STRETCH_CONDENSED,
+	[uiDrawTextStretchSemiCondensed] = DWRITE_FONT_STRETCH_SEMI_CONDENSED,
+	[uiDrawTextStretchNormal] = DWRITE_FONT_STRETCH_NORMAL,
+	[uiDrawTextStretchSemiExpanded] = DWRITE_FONT_STRETCH_SEMI_EXPANDED,
+	[uiDrawTextStretchExpanded] = DWRITE_FONT_STRETCH_EXPANDED,
+	[uiDrawTextStretchExtraExpanded] = DWRITE_FONT_STRETCH_EXTRA_EXPANDED,
+	[uiDrawTextStretchUltraExpanded] = DWRITE_FONT_STRETCH_ULTRA_EXPANDED,
+};
+
+struct lineInfo {
+	size_t startPos;
+	size_t endPos;
+	size_t newlineCount;
+	double x;
+	double y;
+	double width;
+	double height;
+	double baseline;
+};
+
+// this function is deeply indebted to the PadWrite sample: https://github.com/Microsoft/Windows-classic-samples/blob/master/Samples/Win7Samples/multimedia/DirectWrite/PadWrite/TextEditor.cpp
+static void computeLineInfo(uiDrawTextLayout *tl)
+{
+	DWRITE_LINE_METRICS *dlm;
+	size_t nextStart;
+	UINT32 i;
+	DWRITE_HIT_TEST_METRICS htm;
+	UINT32 unused;
+	HRESULT hr;
+
+	// TODO make sure this is legal; if not, switch to GetMetrics() and use its line count field instead
+	hr = tl->layout->GetLineMetrics(NULL, 0, &(tl->nLines));
+	switch (hr) {
+	case S_OK:
+		// TODO what do we do here
+	case E_NOT_SUFFICIENT_BUFFER:
+		break;
+	default:
+		logHRESULT(L"error getting number of lines in IDWriteTextLayout", hr);
+	}
+	tl->lineInfo = (struct lineInfo *) uiAlloc(tl->nLines * sizeof (struct lineInfo), "struct lineInfo[] (text layout)");
+
+	dlm = new DWRITE_LINE_METRICS[tl->nLines];
+	// TODO make sure pasisng NULL here is legal
+	hr = tl->layout->GetLineMetrics(dlm, tl->nLines, NULL);
+	if (hr != S_OK)
+		logHRESULT(L"error getting IDWriteTextLayout line metrics", hr);
+
+	// assume the first line starts at position 0 and the string flow is incremental
+	nextStart = 0;
+	for (i = 0; i < tl->nLines; i++) {
+		tl->lineinfo[i].startPos = nextStart;
+		tl->lineinfo[i].endPos = nextStart + dlm[i].length;
+		tl->lineinfo[i].newlineCount = dlm[i].newlineLength;
+		nextStart = tl->lineinfo[i].endpos;
+
+		hr = layout->HitTestTextRange(line->startPos, (line->endPos - line->newlineCount) - line->startPos,
+			0, 0,
+			&htm, 1, &unused);
+		if (hr == E_NOT_SUFFICIENT_BUFFER)
+			logHRESULT(L"TODO CONTACT ANDLABS — IDWriteTextLayout::HitTestTextRange() can return multiple ranges for a single line", hr);
+		if (hr != S_OK)
+			logHRESULT(L"error getting IDWriteTextLayout line rect", hr);
+		// TODO verify htm.textPosition and htm.length?
+		tl->lineInfo[i].x = htm.left;
+		tl->lineInfo[i].y = htm.top;
+		tl->lineInfo[i].width = htm.width;
+		tl->lineInfo[i].height = htm.height;
+		// TODO verify dlm[i].height == htm.height
+
+		// TODO on Windows 8.1 and/or 10 we can use DWRITE_LINE_METRICS1 to get specific info about the ascent and descent; do we have an alternative?
+		// TODO and even on those platforms can we somehow split tyographic leading from spacing?
+		// TODO and on that note, can we have both line spacing proportionally above and uniformly below?
+		tl->lineinfo[i].baseline = dlm[i].baseline;
+	}
+
+	delete[] dlm;
+}
+
+uiDrawTextLayout *uiDrawNewTextLayout(uiAttributedString *s, uiDrawFontDescriptor *defaultFont, double width)
+{
+	uiDrawTextLayout *tl;
+	WCHAR *wDefaultFamily;
+	DWRITE_WORD_WRAPPING wrap;
+	FLOAT maxWidth;
+	HRESULT hr;
+
+	tl = uiNew(uiDrawTextLayout);
+
+	wDefaultFamily = toUTF16(defaultFont->Family);
+	hr = dwfactory->CreateTextFormat(
+		wDefaultFamily, NULL,
+		// for the most part, DirectWrite weights correlate to ours
+		// the differences:
+		// - Minimum — libui: 0, DirectWrite: 1
+		// - Maximum — libui: 1000, DirectWrite: 999
+		// TODO figure out what to do about this shorter range (the actual major values are the same (but with different names), so it's just a range issue)
+		(DWRITE_FONT_WEIGHT) (defaultFont->Weight),
+		dwriteItalics[defaultFont->Italic],
+		dwriteStrecthes[defaultFont->Stretch],
+		pointSizeToDWriteSize(defaultFont->Size),
+		// see http://stackoverflow.com/questions/28397971/idwritefactorycreatetextformat-failing and https://msdn.microsoft.com/en-us/library/windows/desktop/dd368203.aspx
+		// TODO use the current locale?
+		L"",
+		&(tl->format));
+	if (hr != S_OK)
+		logHRESULT(L"error creating IDWriteTextFormat", hr);
+
+	hr = dwfactory->CreateTextLayout(
+		attrstrUTF16(s), attrstrUTF16Len(s),
+		tl->format,
+		// FLOAT is float, not double, so this should work... TODO
+		FLT_MAX, FLT_MAX,
+		&(tl->layout));
+	if (hr != S_OK)
+		logHRESULT(L"error creating IDWriteTextLayout", hr);
+
+	// and set the width
+	// this is the only wrapping mode (apart from "no wrap") available prior to Windows 8.1 (TODO verify this fact) (TODO this should be the default anyway)
+	wrap = DWRITE_WORD_WRAPPING_WRAP;
+	maxWidth = (FLOAT) width;
+	if (width < 0) {
+		// TODO is this wrapping juggling even necessary?
+		wrap = DWRITE_WORD_WRAPPING_NO_WRAP;
+		// setting the max width in this case technically isn't needed since the wrap mode will simply ignore the max width, but let's do it just to be safe
+		maxWidth = FLT_MAX;		// see TODO above
+	}
+	hr = tl->layout->SetWordWrapping(wrap);
+	if (hr != S_OK)
+		logHRESULT(L"error setting IDWriteTextLayout word wrapping mode", hr);
+	hr = tl->layout->SetMaxWidth(maxWidth);
+	if (hr != S_OK)
+		logHRESULT(L"error setting IDWriteTextLayout max layout width", hr);
+
+	computeLineInfo(tl);
+
+	// and finally copy the UTF-16 to UTF-8 index conversion table
+	tl->u16tou8 = attrstrCopyUTF16ToUTF8(s, &(tl->nu16tou8));
+
+	// TODO can/should this be moved elsewhere?
+	uiFree(wDefaultFamily);
+	return tl;
+}
+
+void uiDrawFreeTextLayout(uiDrawTextLayout *tl)
+{
+	uiFree(tl->u16tou8);
+	uiFree(tl->lineInfo);
+	tl->layout->Release();
+	tl->format->Release();
+	uiFree(tl);
+}
+
+void uiDrawText(uiDrawContext *c, uiDrawTextLayout *tl, double x, double y)
+{
+	D2D1_POINT_2F pt;
+	ID2D1Brush *black;
+
+	// TODO document that fully opaque black is the default text color; figure out whether this is upheld in various scenarios on other platforms
+	// TODO figure out if this needs to be cleaned out
+	black = mkSolidBrush(c->rt, 0.0, 0.0, 0.0, 1.0);
+
+	pt.x = x;
+	pt.y = y;
+	// TODO D2D1_DRAW_TEXT_OPTIONS_NO_SNAP?
+	// TODO D2D1_DRAW_TEXT_OPTIONS_CLIP?
+	// TODO when setting 8.1 as minimum (TODO verify), D2D1_DRAW_TEXT_OPTIONS_ENABLE_COLOR_FONT?
+	// TODO what is our pixel snapping setting related to the OPTIONS enum values?
+	c->rt->DrawTextLayout(pt, tl->layout, black, D2D1_DRAW_TEXT_OPTIONS_NONE);
+
+	black->Release();
+}
+
+// TODO for a single line the height includes the leading; should it? TextEdit on OS X always includes the leading and/or paragraph spacing, otherwise Klee won't work...
+void uiDrawTextLayoutExtents(uiDrawTextLayout *tl, double *width, double *height)
+{
+	DWRITE_TEXT_METRICS metrics;
+	HRESULT hr;
+
+	hr = tl->layout->GetMetrics(&metrics);
+	if (hr != S_OK)
+		logHRESULT(L"error getting IDWriteTextLayout layout metrics", hr);
+	*width = metrics.width;
+	// TODO make sure the behavior of this on empty strings is the same on all platforms (ideally should be 0-width, line height-height; TODO note this in the docs too)
+	*height = metrics.height;
+}
+
+int uiDrawTextLayoutNumLines(uiDrawTextLayout *tl)
+{
+	return tl->nLines;
+}
+
+// DirectWrite doesn't provide a direct way to do this, so we have to do this manually
+void uiDrawTextLayoutLineByteRange(uiDrawTextLayout *tl, int line, size_t *start, size_t *end)
+{
+	*start = tl->lineInfo[line].startPos;
+	*start = tl->u16tou8[*start];
+	*end = tl->lineInfo[line].endPos - tl->lineInfo[line].newlineCount;
+	*end = tl->u16tou8[*end];
+}
+
+void uiDrawTextLayoutLineGetMetrics(uiDrawTextLayout *tl, int line, uiDrawTextLayoutLineMetrics *m)
+{
+	// TODO
+}
+
+void uiDrawTextLayoutByteIndexToGraphemeRect(uiDrawTextLayout *tl, size_t pos, int *line, double *x, double *y, double *width, double *height)
+{
+}
+
+void uiDrawTextLayoutHitTest(uiDrawTextLayout *tl, double x, double y, uiDrawTextLayoutHitTestResult *result)
+{
+	// TODO
+}
+
+void uiDrawTextLayoutByteRangeToRectangle(uiDrawTextLayout *tl, size_t start, size_t end, uiDrawTextLayoutByteRangeRectangle *r)
+{
+}