Background attribute rendering on Windows

windows/attrstr.cpp

@@ -33,6 +33,7 @@ static std::hash<double> doubleHash;
 class combinedEffectsAttr : public IUnknown {
 	ULONG refcount;
 	uiAttribute *colorAttr;
+	uiAttribute *backgroundAttr;
 	uiAttribute *underlineAttr;
 	uiAttribute *underlineColorAttr;
 
@@ -46,6 +47,11 @@ class combinedEffectsAttr : public IUnknown {
 				uiprivAttributeRelease(this->colorAttr);
 			this->colorAttr = uiprivAttributeRetain(a);
 			break;
+		case uiAttributeTypeBackground:
+			if (this->backgroundAttr != NULL)
+				uiprivAttributeRelease(this->backgroundAttr);
+			this->backgroundAttr = uiprivAttributeRetain(a);
+			break;
 		case uiAttributeTypeUnderline:
 			if (this->underlineAttr != NULL)
 				uiprivAttributeRelease(this->underlineAttr);
@@ -74,6 +80,7 @@ public:
 	{
 		this->refcount = 1;
 		this->colorAttr = NULL;
+		this->backgroundAttr = NULL;
 		this->underlineAttr = NULL;
 		this->underlineColorAttr = NULL;
 		this->setAttribute(a);
@@ -83,6 +90,8 @@ public:
 	{
 		if (this->colorAttr != NULL)
 			uiprivAttributeRelease(this->colorAttr);
+		if (this->backgroundAttr != NULL)
+			uiprivAttributeRelease(this->backgroundAttr);
 		if (this->underlineAttr != NULL)
 			uiprivAttributeRelease(this->underlineAttr);
 		if (this->underlineColorAttr != NULL)
@@ -124,6 +133,7 @@ public:
 		combinedEffectsAttr *b;
 
 		b = new combinedEffectsAttr(this->colorAttr);
+		b->setAttribute(this->backgroundAttr);
 		b->setAttribute(this->underlineAttr);
 		b->setAttribute(this->underlineColorAttr);
 		b->setAttribute(a);
@@ -144,6 +154,14 @@ public:
 			ret ^= doubleHash(b);
 			ret ^= doubleHash(a);
 		}
+
+		if (this->backgroundAttr != NULL) {
+			uiAttributeBackground(this->backgroundAttr, &r, &g, &b, &a);
+			ret ^= doubleHash(r);
+			ret ^= doubleHash(g);
+			ret ^= doubleHash(b);
+			ret ^= doubleHash(a);
+		}
 		if (this->underlineAttr != NULL)
 			ret ^= (size_t) uiAttributeUnderline(this->underlineAttr);
 		if (this->underlineColorAttr != NULL) {
@@ -162,6 +180,7 @@ public:
 		if (b == NULL)
 			return false;
 		return combinedEffectsAttr::attrEqual(this->colorAttr, b->colorAttr) &&
+			combinedEffectsAttr::attrEqual(this->backgroundAttr, b->backgroundAttr) &&
 			combinedEffectsAttr::attrEqual(this->underlineAttr, b->underlineAttr) &&
 			combinedEffectsAttr::attrEqual(this->underlineColorAttr, b->underlineColorAttr);
 	}
@@ -177,6 +196,10 @@ public:
 			uiAttributeColor(this->colorAttr, &r, &g, &b, &a);
 			dea->setColor(r, g, b, a);
 		}
+		if (this->backgroundAttr != NULL) {
+			uiAttributeBackground(this->backgroundAttr, &r, &g, &b, &a);
+			dea->setBackground(r, g, b, a);
+		}
 		if (this->underlineAttr != NULL)
 			dea->setUnderline(uiAttributeUnderline(this->underlineAttr));
 		if (this->underlineColorAttr != NULL) {
@@ -338,14 +361,15 @@ static uiForEach processAttribute(const uiAttributedString *s, const uiAttribute
 		// and fall through to set the underline style through the drawing effect
 	case uiAttributeTypeColor:
 	case uiAttributeTypeUnderlineColor:
+	case uiAttributeTypeBackground:
 		// TODO const-correct this properly
 		hr = addEffectAttributeToRange(p, start, end, (uiAttribute *) attr);
 		if (hr != S_OK)
 			logHRESULT(L"error applying effect (color, underline, or underline color) attribute", hr);
 		break;
-	case uiAttributeTypeBackground:
+	// case uiAttributeTypeBackground:
-		addBackgroundParams(p, start, end, attr);
+	// 	addBackgroundParams(p, start, end, attr);
-		break;
+	// 	break;
 	case uiAttributeTypeFeatures:
 		// only generate an attribute if not NULL
 		// TODO do we still need to do this or not...

windows/attrstr.hpp

@@ -39,6 +39,12 @@ class drawingEffectsAttr : public IUnknown {
 	double b;
 	double a;
 
+	bool hasBackground;
+	double br;
+	double bg;
+	double bb;
+	double ba;
+
 	bool hasUnderline;
 	uiUnderline u;
 
@@ -56,9 +62,11 @@ public:
 	virtual ULONG STDMETHODCALLTYPE Release(void);
 
 	void setColor(double r, double g, double b, double a);
+	void setBackground(double r, double g, double b, double a);
 	void setUnderline(uiUnderline u);
 	void setUnderlineColor(double r, double g, double b, double a);
 	HRESULT mkColorBrush(ID2D1RenderTarget *rt, ID2D1SolidColorBrush **b);
+	HRESULT mkBackgroundBrush(ID2D1RenderTarget *rt, ID2D1SolidColorBrush **b);
 	HRESULT underline(uiUnderline *u);
 	HRESULT mkUnderlineBrush(ID2D1RenderTarget *rt, ID2D1SolidColorBrush **b);
 };

windows/drawtext.cpp

@@ -143,6 +143,7 @@ drawingEffectsAttr::drawingEffectsAttr(void)
 {
 	this->refcount = 1;
 	this->hasColor = false;
+	this->hasBackground = false;
 	this->hasUnderline = false;
 	this->hasUnderlineColor = false;
 }
@@ -185,6 +186,15 @@ void drawingEffectsAttr::setColor(double r, double g, double b, double a)
 	this->a = a;
 }
 
+void drawingEffectsAttr::setBackground(double r, double g, double b, double a)
+{
+	this->hasBackground = true;
+	this->br = r;
+	this->bg = g;
+	this->bb = b;
+	this->ba = a;
+}
+
 void drawingEffectsAttr::setUnderline(uiUnderline u)
 {
 	this->hasUnderline = true;
@@ -209,6 +219,15 @@ HRESULT drawingEffectsAttr::mkColorBrush(ID2D1RenderTarget *rt, ID2D1SolidColorB
 	return mkSolidBrush(rt, this->r, this->g, this->b, this->a, b);
 }
 
+HRESULT drawingEffectsAttr::mkBackgroundBrush(ID2D1RenderTarget *rt, ID2D1SolidColorBrush **b)
+{
+	if (!this->hasBackground) {
+		*b = NULL;
+		return S_OK;
+	}
+	return mkSolidBrush(rt, this->br, this->bg, this->bb, this->ba, b);
+}
+
 HRESULT drawingEffectsAttr::underline(uiUnderline *u)
 {
 	if (u == NULL)
@@ -316,28 +335,57 @@ public:
 	{
 		D2D1_POINT_2F baseline;
 		drawingEffectsAttr *dea = (drawingEffectsAttr *) clientDrawingEffect;
-		ID2D1SolidColorBrush *brush;
+		ID2D1SolidColorBrush *foregroundBrush;
+		ID2D1SolidColorBrush *backgroundBrush;
 
 		baseline.x = baselineOriginX;
 		baseline.y = baselineOriginY;
-		brush = NULL;
+		foregroundBrush = NULL;
+		backgroundBrush = NULL;
 		if (dea != NULL) {
 			HRESULT hr;
 
-			hr = dea->mkColorBrush(this->rt, &brush);
+			hr = dea->mkColorBrush(this->rt, &foregroundBrush);
+			if (hr != S_OK)
+				return hr;
+
+			hr = dea->mkBackgroundBrush(this->rt, &backgroundBrush);
 			if (hr != S_OK)
 				return hr;
 		}
-		if (brush == NULL) {
+		if (foregroundBrush == NULL) {
-			brush = this->black;
+			foregroundBrush = this->black;
-			brush->AddRef();
+			foregroundBrush->AddRef();
+		}
+		if (backgroundBrush != nullptr) {
+			// Get width of text
+			float totalWidth = 0;
+
+			for (UINT32 index = 0; index < glyphRun->glyphCount; index++)
+			{
+				totalWidth += glyphRun->glyphAdvances[index];
+			}
+
+			// Get height of text
+			DWRITE_FONT_METRICS fontMetrics;
+			glyphRun->fontFace->GetMetrics(&fontMetrics);
+			float adjust = glyphRun->fontEmSize / fontMetrics.designUnitsPerEm;
+			float ascent = adjust * fontMetrics.ascent;
+			float descent = adjust * fontMetrics.descent;
+			D2D1_RECT_F rect = D2D1::RectF(baselineOriginX,
+									 baselineOriginY - ascent,
+									 baselineOriginX + totalWidth,
+									 baselineOriginY + descent);
+
+			// Fill Rectangle
+			this->rt->FillRectangle(rect, backgroundBrush);
 		}
 		this->rt->DrawGlyphRun(
 			baseline,
 			glyphRun,
-			brush,
+			foregroundBrush,
 			measuringMode);
-		brush->Release();
+		foregroundBrush->Release();
 		return S_OK;
 	}