Initial commit of the extended OSWindow generic renderer API with sup…

…port for text rendering.

src/Fonts-Abstract/AbstractFont.class.st

@@ -92,6 +92,18 @@ AbstractFont >> basicDescentOf: aCharacter [
 
 ]
 
+{ #category : #'glyph lookup' }
+AbstractFont >> characterFormAt: aCharacter [
+	^ nil
+]
+
+{ #category : #'glyph lookup' }
+AbstractFont >> characterRenderingOptimizedFormAt: aCharacter [
+	"This method returns a version of the character form which is optimized for rendering
+	through an accelerated alpha blending equation in the style of the OpenGL glBlendFuncSeparate."
+	^ (self characterFormAt: aCharacter) ifNotNil: [:form | form invertedAndAlphaMultiplied]
+]
+
 { #category : #accessing }
 AbstractFont >> characterToGlyphMap [
 	"Return the character to glyph mapping table. If the table is not provided the character scanner will query the font directly for the width of each individual character."
@@ -137,6 +149,11 @@ AbstractFont >> familyName [
 	^self subclassResponsibility
 ]
 
+{ #category : #testing }
+AbstractFont >> hasSubPixelAntiAliasing [
+	^ false
+]
+
 { #category : #accessing }
 AbstractFont >> height [
 	"Answer the height of the receiver, total of maximum extents of 
@@ -196,6 +213,16 @@ AbstractFont >> releaseCachedState [
 
 ]
 
+{ #category : #metrics }
+AbstractFont >> strikeoutThickness [
+	^ 0
+]
+
+{ #category : #metrics }
+AbstractFont >> strikeoutTop [
+	^ 0
+]
+
 { #category : #accessing }
 AbstractFont >> textStyle [
 	^ TextStyle actualTextStyles detect:
@@ -208,6 +235,16 @@ AbstractFont >> textStyleName [
 	^self familyName
 ]
 
+{ #category : #metrics }
+AbstractFont >> underlineThickness [
+	^ 0
+]
+
+{ #category : #metrics }
+AbstractFont >> underlineTop [
+	^ 0
+]
+
 { #category : #'development support' }
 AbstractFont >> validate [
 	"Concrete classes should override this to provide validation"

src/Fonts-Infrastructure/LogicalFont.class.st

@@ -377,6 +377,11 @@ LogicalFont >> characterFormAt: aCharacter [
 	^self realFont characterFormAt: aCharacter
 ]
 
+{ #category : #'glyph lookup' }
+LogicalFont >> characterRenderingOptimizedFormAt: aCharacter [
+	^ self realFont characterRenderingOptimizedFormAt: aCharacter
+]
+
 { #category : #'forwarded to realFont' }
 LogicalFont >> characterToGlyphMap [
 	"Provided only for accelerating text scanning thru primitive 103 - see super."
@@ -605,6 +610,11 @@ LogicalFont >> hasGlyphsForAll: asciiString [
 	^self realFont hasGlyphsForAll: asciiString
 ]
 
+{ #category : #testing }
+LogicalFont >> hasSubPixelAntiAliasing [
+	^ self realFont hasSubPixelAntiAliasing
+]
+
 { #category : #'forwarded to realFont' }
 LogicalFont >> height [
 	^self realFont height
@@ -790,6 +800,26 @@ LogicalFont >> stretchValue: anObject [
 	stretchValue := anObject
 ]
 
+{ #category : #metrics }
+LogicalFont >> strikeoutThickness [
+	^ self realFont strikeoutThickness
+]
+
+{ #category : #metrics }
+LogicalFont >> strikeoutTop [
+	^ self realFont strikeoutTop
+]
+
+{ #category : #metrics }
+LogicalFont >> underlineThickness [
+	^ self realFont underlineThickness
+]
+
+{ #category : #metrics }
+LogicalFont >> underlineTop [
+	^ self realFont underlineTop
+]
+
 { #category : #accessing }
 LogicalFont >> weightValue [
 	"Answer the value of weightValue"

src/FreeType/FreeTypeFont.class.st

@@ -96,6 +96,17 @@ FreeTypeFont >> characterFormAt: aCharacter [
 				subpixelPosition: 0]
 ]
 
+{ #category : #'glyph lookup' }
+FreeTypeFont >> characterRenderingOptimizedFormAt: aCharacter [
+	FreeTypeSettings current useSubPixelAntiAliasing ifFalse: [ ^ super characterRenderingOptimizedFormAt: aCharacter ].
+
+	^ (self 
+		glyphOf: aCharacter 
+		destDepth: 32 
+		colorValue: (Color white pixelValueForDepth: 32)
+		subpixelPosition: 0) withAlphaExtractedFromSubpixelRendering
+]
+
 { #category : #accessing }
 FreeTypeFont >> clearCachedMetrics [
 	widthAndKernedWidthCache := cachedHeight := cachedAscent := cachedDescent := subPixelPositioned := nil
@@ -469,6 +480,11 @@ FreeTypeFont >> hasGlyphsForAll: asciiString [
 	^true
 ]
 
+{ #category : #testing }
+FreeTypeFont >> hasSubPixelAntiAliasing [
+	^ FreeTypeSettings current useSubPixelAntiAliasing
+]
+
 { #category : #comparing }
 FreeTypeFont >> hash [
 	^pointSize hash
@@ -786,6 +802,16 @@ FreeTypeFont >> simulatedItalicSlant [
 	^0
 ]
 
+{ #category : #metrics }
+FreeTypeFont >> strikeoutThickness [
+	^ self underlineThickness
+]
+
+{ #category : #metrics }
+FreeTypeFont >> strikeoutTop [
+	^ (((self face ascender / 4) * self pixelSize / self face unitsPerEm) negated - (self strikeoutThickness/2)) rounded.
+]
+
 { #category : #'glyph lookup' }
 FreeTypeFont >> subGlyphOf: aCharacter colorValue: aColorValue mono: monoBoolean subpixelPosition: sub [
 
@@ -816,6 +842,16 @@ FreeTypeFont >> subPixelPositioned [
 			subPixelPositioned := settings hinting not or:[settings lightHinting]]
 ]
 
+{ #category : #metrics }
+FreeTypeFont >> underlineThickness [
+	^ self face underlineThickness * self pixelSize / self face unitsPerEm.
+]
+
+{ #category : #metrics }
+FreeTypeFont >> underlineTop [
+	^ ((self face underlinePosition * self pixelSize / self face unitsPerEm) negated - (self underlineThickness/2)) rounded + 1 "needs the +1 , possibly because glyph origins are moved down by 1 so that their baselines line up with strike fonts"
+]
+
 { #category : #validation }
 FreeTypeFont >> validate [ 
 	self face validate

src/FreeType/GlyphForm.class.st

@@ -38,6 +38,17 @@ GlyphForm >> asFormOfDepth: d [
 	^newForm
 ]
 
+{ #category : #converting }
+GlyphForm >> invertedAndAlphaMultiplied [
+	| result |
+	result := super invertedAndAlphaMultiplied.
+	^ (self class extent: result extent depth: result depth bits: result bits)
+		offset: offset;
+		advance: advance;
+		linearAdvance: linearAdvance;
+		yourself
+]
+
 { #category : #accessing }
 GlyphForm >> linearAdvance [
 	^linearAdvance
@@ -48,3 +59,25 @@ GlyphForm >> linearAdvance [
 GlyphForm >> linearAdvance: aNumber [
 	^linearAdvance := aNumber
 ]
+
+{ #category : #converting }
+GlyphForm >> withAlphaExtractedFromSubpixelRendering [
+	| result |
+	"Take the maximum of r,g,b as the alpha. Then multiply by a."
+	result := self collectColors: [:c |
+		| r g b a|
+		r := c red.
+		g := c green.
+		b := c blue.
+		a := c alpha.
+		a := ((r max: g) max: b) * a.
+
+		Color r: r g: g b: b alpha: a
+	].
+
+	^ (self class extent: result extent depth: result depth bits: result bits)
+		offset: offset;
+		advance: advance;
+		linearAdvance: linearAdvance;
+		yourself
+]

src/Graphics-Display Objects/Form.class.st

@@ -277,6 +277,15 @@ Form >> allocateForm: extentPoint [
 	^Form extent: extentPoint depth: self nativeDepth
 ]
 
+{ #category : #converting }
+Form >> alphaMultiplied [
+	^ (self asFormOfDepth: 32) collectColors: [ :c |
+		| a |
+		a := c alpha.
+		Color r: c red * a g: c green * a b: c blue * a alpha: a
+	]
+]
+
 { #category : #converting }
 Form >> as8BitColorForm [
 	"Simple conversion of zero pixels to transparent.  Force it to 8 bits."
@@ -1432,6 +1441,15 @@ Form >> innerPixelRectFor: pv orNot: not [
 			(xTally findLast: [:t | t>0])@(yTally findLast: [:t | t>0])
 ]
 
+{ #category : #converting }
+Form >> invertedAndAlphaMultiplied [
+	^ (self asFormOfDepth: 32) collectColors: [ :c |
+		| a |
+		a := c alpha.
+		Color r: (1.0 - c red) * a g: (1.0 - c green) * a b: (1.0 - c blue) * a alpha: a
+	]
+]
+
 { #category : #testing }
 Form >> isAllWhite [
 	"Answer whether all bits in the receiver are white"
@@ -2560,6 +2578,20 @@ Form >> wipeImage: otherImage at: topLeft delta: delta clippingBox: clipBox [
 			ifFalse: [nil]]
 ]
 
+{ #category : #converting }
+Form >> withAlphaExtractedFromSubpixelRendering [
+	^ (self asFormOfDepth: 32) collectColors: [ :c |
+		| r g b a|
+		r := c red.
+		g := c green.
+		b := c blue.
+		a := c alpha.
+		a := ((r max: g) max: b) * a.
+
+		Color r: r g: g b: b alpha: a
+	]
+]
+
 { #category : #'file in/out' }
 Form >> writeAttributesOn: file [
 	self unhibernate.

src/OSWindow-SDL2/AbstractFont.extension.st

@@ -0,0 +1,6 @@
+Extension { #name : #AbstractFont }
+
+{ #category : #'*OSWindow-SDL2' }
+AbstractFont >> createCachedFontForSDL2GenericRenderer: renderer [
+	^ renderer createTextureAtlasFontCacheFor: self
+]

src/OSWindow-SDL2/LogicalFont.extension.st

@@ -0,0 +1,6 @@
+Extension { #name : #LogicalFont }
+
+{ #category : #'*OSWindow-SDL2' }
+LogicalFont >> createCachedFontForSDL2GenericRenderer: renderer [
+	^ renderer getOrCreateCachedFontFor: self realFont
+]

src/OSWindow-SDL2/OSSDL2AthensRenderer.class.st

@@ -55,7 +55,6 @@ OSSDL2AthensRenderer >> initializeWindowHandle: aBackendWindow [
 	renderer := backendWindow sdl2Window createDefaultRenderer.
 	self resetResources.
 
-
 ]
 
 { #category : #drawing }