Issue #5: Add Framebuffer:getImageData()

src/modules/graphics/opengl/Framebuffer.cpp

@@ -1,6 +1,8 @@
 #include "Framebuffer.h"
 #include <common/Matrix.h>
 
+#include <string.h>
+
 #include <iostream>
 #include <string>
 #include <sstream>
@@ -275,6 +277,37 @@ namespace opengl
 		glPopMatrix();
 	}
 
+	love::image::ImageData * Framebuffer::getImageData(love::image::Image * image)
+	{
+		int row = 4 * width;
+		int size = row * height;
+
+		// see Graphics::newScreenshot. OpenGL reads from lower-left,
+		// but we need the pixels from upper-left.
+		GLubyte* pixels = new GLubyte[size];
+		GLubyte* screenshot = new GLubyte[size];
+
+		strategy->bindFBO( fbo );
+		glReadPixels(0, 0, width, height, GL_RGBA, GL_UNSIGNED_BYTE, pixels);
+		if (current)
+			strategy->bindFBO( current->fbo );
+		else
+			strategy->bindFBO( 0 );
+
+		GLubyte* src = pixels - row; // second line of buffer
+		GLubyte* dst = screenshot + size; // end of buffer
+
+		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;
+	}
+
 } // opengl
 } // graphics
 } // love

src/modules/graphics/opengl/Framebuffer.h

@@ -2,7 +2,8 @@
 #define LOVE_GRAPHICS_FRAMEBUFFER_H
 
 #include <graphics/Drawable.h>
-#include <graphics/Volatile.h>
+#include <image/Image.h>
+#include <image/ImageData.h>
 #include <common/math.h>
 #include <map>
 #include "GLee.h"
@@ -29,7 +30,7 @@ namespace opengl
 		void stopGrab();
 
 		virtual void draw(float x, float y, float angle, float sx, float sy, float ox, float oy) const;
-
+		love::image::ImageData * getImageData(love::image::Image * image);
 
 	private:
 		GLsizei width;

src/modules/graphics/opengl/wrap_Framebuffer.cpp

@@ -32,8 +32,18 @@ namespace opengl
 		return 0;
 	}
 
+	int w_Framebuffer_getImageData(lua_State * L)
+	{
+		Framebuffer * fbo = luax_checkfbo(L, 1);
+		love::image::Image * image = luax_getmodule<love::image::Image>(L, "image", MODULE_IMAGE_T);
+		love::image::ImageData * img = fbo->getImageData( image );
+		luax_newtype(L, "ImageData", IMAGE_IMAGE_DATA_T, (void *)img);
+		return 1;
+	}
+
 	static const luaL_Reg functions[] = {
 		{ "renderTo", w_Framebuffer_renderTo },
+		{ "getImageData", w_Framebuffer_getImageData },
 		{ 0, 0 }
 	};
 

src/modules/graphics/opengl/wrap_Framebuffer.h

@@ -14,6 +14,7 @@ namespace opengl
 	//see Framebuffer.h
 	Framebuffer * luax_checkfbo(lua_State * L, int idx);
 	int w_Framebuffer_renderTo(lua_State * L);
+	int w_Framebuffer_getImageData(lua_State * L);
 	int luaopen_framebuffer(lua_State * L);
 
 } // opengl