Revert Canvas flipping (commits 9cb824e2fa84, e0234edd0026) in order to fix issue #324.

src/modules/graphics/Quad.h

@@ -50,6 +50,11 @@ namespace graphics
 
 		virtual void flip(bool x, bool y) = 0;
 
+		/**
+		 * Mirror texture coordinates around 0.5
+		 */
+		virtual void mirror(bool x, bool y) = 0;
+
 		/**
 		* Gets a pointer to the vertices.
 		**/

src/modules/graphics/opengl/Canvas.cpp

@@ -195,10 +195,10 @@ namespace opengl
 		vertices[3].x = w; vertices[3].y = 0;
 
 		// texture coordinates
-		vertices[0].s = 0;     vertices[0].t = 0;
-		vertices[1].s = 0;     vertices[1].t = 1;
-		vertices[2].s = 1;     vertices[2].t = 1;
-		vertices[3].s = 1;     vertices[3].t = 0;
+		vertices[0].s = 0;     vertices[0].t = 1;
+		vertices[1].s = 0;     vertices[1].t = 0;
+		vertices[2].s = 1;     vertices[2].t = 0;
+		vertices[3].s = 1;     vertices[3].t = 1;
 
 		loadStrategy();
 
@@ -246,8 +246,8 @@ namespace opengl
 		glPushMatrix();
 		glLoadIdentity();
 		
-		// Set up upside-down orthographic view (no depth)
-		glOrtho(0.0, width, 0.0, height, -1.0, 1.0);
+		// Set up orthographic view (no depth)
+		glOrtho(0.0, width, height, 0.0, -1.0, 1.0);
 		
 		// Switch back to modelview matrix
 		glMatrixMode(GL_MODELVIEW);
@@ -297,15 +297,20 @@ namespace opengl
 	void Canvas::drawq(love::graphics::Quad * quad, float x, float y, float angle, float sx, float sy, float ox, float oy, float kx, float ky) const
 	{
 		static Matrix t;
+		quad->mirror(false, true);
 		const vertex * v = quad->getVertices();
 
 		t.setTransformation(x, y, angle, sx, sy, ox, oy, kx, ky);
 		drawv(t, v);
+		quad->mirror(false, true);
 	}
 
 	love::image::ImageData * Canvas::getImageData(love::image::Image * image)
 	{
-		GLubyte * pixels = new GLubyte[4*width*height];
+		int row = 4 * width;
+		int size = row * height;
+		GLubyte* pixels = new GLubyte[size];
+		GLubyte* screenshot = new GLubyte[size];
 
 		strategy->bindFBO( fbo );
 		glReadPixels(0, 0, width, height, GL_RGBA, GL_UNSIGNED_BYTE, pixels);
@@ -314,8 +319,15 @@ namespace opengl
 		else
 			strategy->bindFBO( 0 );
 
-		love::image::ImageData * img = image->newImageData(width, height, (void*)pixels);
+		GLubyte * src = pixels - row; // second line of source image
+		GLubyte * dst = screenshot + size; // last row of destination image
+
+		for (int i = 0; i < height; ++i)
+			memcpy(dst -= row, src += row, row);
+
+		love::image::ImageData* img = image->newImageData(width, height, (void*)screenshot);
 		
+		delete[] screenshot;
 		delete[] pixels;
 
 		return img;

src/modules/graphics/opengl/Quad.cpp

@@ -1,14 +1,14 @@
 /**
 * Copyright (c) 2006-2011 LOVE Development Team
-* 
+*
 * This software is provided 'as-is', without any express or implied
 * warranty.  In no event will the authors be held liable for any damages
 * arising from the use of this software.
-* 
+*
 * Permission is granted to anyone to use this software for any purpose,
 * including commercial applications, and to alter it and redistribute it
 * freely, subject to the following restrictions:
-* 
+*
 * 1. The origin of this software must not be misrepresented; you must not
 *    claim that you wrote the original software. If you use this software
 *    in a product, an acknowledgment in the product documentation would be
@@ -36,7 +36,7 @@ namespace opengl
 	Quad::Quad(const Viewport & v, float sw, float sh)
 		: sw(sw), sh(sh)
 	{
-		memset(vertices, 255, sizeof(vertex)*4);
+		memset(vertices, 255, sizeof(vertex)*NUM_VERTICES);
 		refresh(v, sw, sh);
 	}
 
@@ -53,22 +53,22 @@ namespace opengl
 		}
 		viewport = v;
 
-		vertices[0].x = 0; 
+		vertices[0].x = 0;
 		vertices[0].y = 0;
-		vertices[1].x = 0; 
+		vertices[1].x = 0;
 		vertices[1].y = v.h;
-		vertices[2].x = v.w; 
+		vertices[2].x = v.w;
 		vertices[2].y = v.h;
-		vertices[3].x = v.w; 
+		vertices[3].x = v.w;
 		vertices[3].y = 0;
-		
-		vertices[0].s = v.x/sw; 
+
+		vertices[0].s = v.x/sw;
 		vertices[0].t = v.y/sh;
-		vertices[1].s = v.x/sw; 
+		vertices[1].s = v.x/sw;
 		vertices[1].t = (v.y+v.h)/sh;
-		vertices[2].s = (v.x+v.w)/sw; 
+		vertices[2].s = (v.x+v.w)/sw;
 		vertices[2].t = (v.y+v.h)/sh;
-		vertices[3].s = (v.x+v.w)/sw; 
+		vertices[3].s = (v.x+v.w)/sw;
 		vertices[3].t = v.y/sh;
 	}
 
@@ -79,15 +79,15 @@ namespace opengl
 
 	Quad::Viewport Quad::getViewport() const
 	{
-		return viewport;	
+		return viewport;
 	}
-	
+
 	void Quad::flip(bool x, bool y)
 	{
 		vertex temp[4];
 		if (x)
 		{
-			memcpy(temp, vertices, sizeof(vertex)*4);
+			memcpy(temp, vertices, sizeof(vertex)*NUM_VERTICES);
 			vertices[0].s = temp[3].s; vertices[0].t = temp[3].t;
 			vertices[1].s = temp[2].s; vertices[1].t = temp[2].t;
 			vertices[2].s = temp[1].s; vertices[2].t = temp[1].t;
@@ -95,7 +95,7 @@ namespace opengl
 		}
 		if (y)
 		{
-			memcpy(temp, vertices, sizeof(vertex)*4);
+			memcpy(temp, vertices, sizeof(vertex)*NUM_VERTICES);
 			vertices[0].s = temp[1].s; vertices[0].t = temp[1].t;
 			vertices[1].s = temp[0].s; vertices[1].t = temp[0].t;
 			vertices[2].s = temp[3].s; vertices[2].t = temp[3].t;
@@ -103,6 +103,16 @@ namespace opengl
 		}
 	}
 
+	void Quad::mirror(bool x, bool y)
+	{
+		for (size_t i = 0; i < NUM_VERTICES; ++i) {
+			if (x)
+				vertices[i].s = 1.0 - vertices[i].s;
+			if (y)
+				vertices[i].s = 1.0 - vertices[i].s;
+		}
+	}
+
 	const vertex * Quad::getVertices() const
 	{
 		return vertices;

src/modules/graphics/opengl/Quad.h

@@ -1,14 +1,14 @@
 /**
 * Copyright (c) 2006-2011 LOVE Development Team
-* 
+*
 * This software is provided 'as-is', without any express or implied
 * warranty.  In no event will the authors be held liable for any damages
 * arising from the use of this software.
-* 
+*
 * Permission is granted to anyone to use this software for any purpose,
 * including commercial applications, and to alter it and redistribute it
 * freely, subject to the following restrictions:
-* 
+*
 * 1. The origin of this software must not be misrepresented; you must not
 *    claim that you wrote the original software. If you use this software
 *    in a product, an acknowledgment in the product documentation would be
@@ -33,11 +33,12 @@ namespace opengl
 {
 	class Quad : public love::graphics::Quad
 	{
-		
+
 	protected:
-		
-		vertex vertices[4];
-		
+
+		static const unsigned int NUM_VERTICES = 4;
+		vertex vertices[NUM_VERTICES];
+
 		Viewport viewport;
 		float sw, sh;
 
@@ -47,7 +48,7 @@ namespace opengl
 		* Creates a new Quad of size (w,h), using (x,y) as the top-left
 		* anchor point in the source image. The size of the source image is
 		* is specified by (sw,sh).
-		* 
+		*
 		* @param sw Width of the source image.
 		* @param sh Height of the source image.
 		**/
@@ -61,6 +62,7 @@ namespace opengl
 		Viewport getViewport() const;
 
 		void flip(bool x, bool y);
+		void mirror(bool x, bool y);
 
 		/**
 		* Gets a pointer to the vertices.