Added stack type enums to love.graphics.push (resolves issue #906.) Current enums are "transform" and "all". "transform" is the default (for compatibility.) When love.graphics.push("all") is used, love.graphics.pop() will restore all love.graphics module state to what it was when push was called.

Updated the graphics code to use a custom matrix stack rather than OpenGL1's APIs.

src/modules/graphics/opengl/Graphics.h

@@ -57,48 +57,7 @@ namespace opengl
 // During display mode changing, certain
 // variables about the OpenGL context are
 // lost.
-struct DisplayState
-{
-	// Colors.
-	Color color;
-	Color backgroundColor;
 
-	// Blend mode.
-	Graphics::BlendMode blendMode;
-
-	// Line.
-	Graphics::LineStyle lineStyle;
-	Graphics::LineJoin lineJoin;
-
-	// Point.
-	float pointSize;
-	Graphics::PointStyle pointStyle;
-
-	// Scissor.
-	bool scissor;
-	OpenGL::Viewport scissorBox;
-
-	// Color mask.
-	bool colorMask[4];
-
-	bool wireframe;
-
-	// Default values.
-	DisplayState()
-	{
-		color.set(255,255,255,255);
-		backgroundColor.set(0, 0, 0, 255);
-		blendMode = Graphics::BLEND_ALPHA;
-		lineStyle = Graphics::LINE_SMOOTH;
-		lineJoin  = Graphics::LINE_JOIN_MITER;
-		pointSize = 1.0f;
-		pointStyle = Graphics::POINT_SMOOTH;
-		scissor = false;
-		colorMask[0] = colorMask[1] = colorMask[2] = colorMask[3] = true;
-		wireframe = false;
-	}
-
-};
 
 class Graphics : public love::graphics::Graphics
 {
@@ -110,10 +69,6 @@ public:
 	// Implements Module.
 	const char *getName() const;
 
-	DisplayState saveState();
-
-	void restoreState(const DisplayState &s);
-
 	virtual void setViewportSize(int width, int height);
 	virtual bool setMode(int width, int height, bool &sRGB);
 	virtual void unSetMode();
@@ -246,10 +201,21 @@ public:
 	 **/
 	Font *getFont() const;
 
+	void setShader(Shader *shader);
+	void setShader();
+
+	Shader *getShader() const;
+
+	void setCanvas(Canvas *canvas);
+	void setCanvas(const std::vector<Canvas *> &canvases);
+	void setCanvas();
+
+	std::vector<Canvas *> getCanvas() const;
+
 	/**
 	 * Sets the enabled color components when rendering.
 	 **/
-	void setColorMask(bool r, bool g, bool b, bool a);
+	void setColorMask(const bool mask[4]);
 
 	/**
 	 * Gets the current color mask.
@@ -460,8 +426,9 @@ public:
 	 **/
 	bool isSupported(Support feature) const;
 
-	void push();
+	void push(StackType type = STACK_TRANSFORM);
 	void pop();
+
 	void rotate(float r);
 	void scale(float x, float y = 1.0f);
 	void translate(float x, float y);
@@ -470,17 +437,50 @@ public:
 
 private:
 
-	Font *currentFont;
+	struct DisplayState
+	{
+		// Colors.
+		Color color;
+		Color backgroundColor;
+
+		// Blend mode.
+		BlendMode blendMode;
+
+		// Line.
+		float lineWidth;
+		LineStyle lineStyle;
+		LineJoin lineJoin;
+
+		// Point.
+		float pointSize;
+		PointStyle pointStyle;
+
+		// Scissor.
+		bool scissor;
+		OpenGL::Viewport scissorBox;
+
+		Font *font;
+		Shader *shader;
+		std::vector<Canvas *> canvases;
+
+		// Color mask.
+		bool colorMask[4];
+
+		bool wireframe;
+
+		DisplayState();
+		DisplayState(const DisplayState &other);
+		~DisplayState();
+
+		DisplayState &operator = (const DisplayState &other);
+	};
+
+	void restoreState(const DisplayState &s);
+	void restoreStateChecked(const DisplayState &s);
+
 	love::window::Window *currentWindow;
 
 	std::vector<double> pixel_size_stack; // stores current size of a pixel (needed for line drawing)
-	LineStyle lineStyle;
-	LineJoin lineJoin;
-	float lineWidth;
-	GLint matrixLimit;
-	GLint userMatrices;
-	bool colorMask[4];
-	bool wireframe;
 
 	int width;
 	int height;
@@ -488,7 +488,10 @@ private:
 
 	bool activeStencil;
 
-	DisplayState savedState;
+	std::vector<DisplayState> states;
+	std::vector<StackType> stackTypes; // Keeps track of the pushed stack types.
+
+	static const size_t MAX_USER_STACK_DEPTH = 64;
 
 }; // Graphics