From 4cb247b3ea6fafdbc1c064dd0d14f1d716ee8aaf Mon Sep 17 00:00:00 2001
From: Bill Meltsner <bill@meltsner.com>
Date: Tue, 4 Oct 2011 11:34:33 -0400
Subject: [PATCH] Change how Canvas is flipped and add Canvas::drawq

---
 src/modules/graphics/opengl/Canvas.cpp | 55 ++++++++++++++++----------
 src/modules/graphics/opengl/Canvas.h   | 12 ++++++
 2 files changed, 47 insertions(+), 20 deletions(-)

diff --git a/src/modules/graphics/opengl/Canvas.cpp b/src/modules/graphics/opengl/Canvas.cpp
index 60cf10ca2..70d66c13c 100644
--- a/src/modules/graphics/opengl/Canvas.cpp
+++ b/src/modules/graphics/opengl/Canvas.cpp
@@ -177,10 +177,10 @@ namespace opengl
 		vertices[3].x = w; vertices[3].y = 0;
 
 		// texture coordinates
-		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;
+		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;
 
 		loadStrategy();
 
@@ -228,8 +228,8 @@ namespace opengl
 		glPushMatrix();
 		glLoadIdentity();
 		
-		// Set up orthographic view (no depth)
-		glOrtho(0.0, width, height, 0.0, -1.0, 1.0);
+		// Set up upside-down orthographic view (no depth)
+		glOrtho(0.0, width, 0.0, height, -1.0, 1.0);
 		
 		// Switch back to modelview matrix
 		glMatrixMode(GL_MODELVIEW);
@@ -273,20 +273,16 @@ namespace opengl
 		static Matrix t;
 		t.setTransformation(x, y, angle, sx, sy, ox, oy, kx, ky);
 
-		glPushMatrix();
-		glMultMatrixf((const GLfloat*)t.getElements());
-
-		glBindTexture(GL_TEXTURE_2D, img);
-
-		glEnableClientState(GL_VERTEX_ARRAY);
-		glEnableClientState(GL_TEXTURE_COORD_ARRAY);
-		glVertexPointer(2, GL_FLOAT, sizeof(vertex), (GLvoid*)&vertices[0].x);
-		glTexCoordPointer(2, GL_FLOAT, sizeof(vertex), (GLvoid*)&vertices[0].s);
-		glDrawArrays(GL_QUADS, 0, 4);
-		glDisableClientState(GL_TEXTURE_COORD_ARRAY);
-		glDisableClientState(GL_VERTEX_ARRAY);
-
-		glPopMatrix();
+		drawv(t, vertices);
+	}
+	
+	void Canvas::drawq(Quad * quad, float x, float y, float angle, float sx, float sy, float ox, float oy, float kx, float ky) const
+	{
+		static Matrix t;
+		const vertex * v = quad->getVertices();
+		
+		t.setTransformation(x, y, angle, sx, sy, ox, oy, kx, ky);
+		drawv(t, v);
 	}
 
 	love::image::ImageData * Canvas::getImageData(love::image::Image * image)
@@ -399,6 +395,25 @@ namespace opengl
 	{
 		return height;
 	}
+	
+	void Canvas::drawv(const Matrix & t, const vertex * v) const
+	{
+		glPushMatrix();
+		
+		glMultMatrixf((const GLfloat*)t.getElements());
+		
+		glBindTexture(GL_TEXTURE_2D, img);
+		
+		glEnableClientState(GL_VERTEX_ARRAY);
+		glEnableClientState(GL_TEXTURE_COORD_ARRAY);
+		glVertexPointer(2, GL_FLOAT, sizeof(vertex), (GLvoid*)&v[0].x);
+		glTexCoordPointer(2, GL_FLOAT, sizeof(vertex), (GLvoid*)&v[0].s);
+		glDrawArrays(GL_QUADS, 0, 4);
+		glDisableClientState(GL_TEXTURE_COORD_ARRAY);
+		glDisableClientState(GL_VERTEX_ARRAY);
+		
+		glPopMatrix();
+	}
 
 } // opengl
 } // graphics
diff --git a/src/modules/graphics/opengl/Canvas.h b/src/modules/graphics/opengl/Canvas.h
index a3ef7c323..40b9aed2d 100644
--- a/src/modules/graphics/opengl/Canvas.h
+++ b/src/modules/graphics/opengl/Canvas.h
@@ -8,7 +8,9 @@
 #include <image/Image.h>
 #include <image/ImageData.h>
 #include <common/math.h>
+#include <common/Matrix.h>
 #include "GLee.h"
+#include "Quad.h"
 
 namespace love
 {
@@ -35,6 +37,14 @@ namespace opengl
 		void clear(const Color& c);
 
 		virtual void draw(float x, float y, float angle, float sx, float sy, float ox, float oy, float kx, float ky) const;
+
+		/**
+		* This function draws a section of the canvas using a Quad object.
+		*
+		* @param quad Represents the region of the Canvas to draw.
+		**/
+		void drawq(Quad * quad, float x, float y, float angle, float sx, float sy, float ox, float oy, float kx, float ky) const;
+		
 		love::image::ImageData * getImageData(love::image::Image * image);
 
 		void setFilter(const Image::Filter &f);
@@ -67,6 +77,8 @@ namespace opengl
 			Image::Filter filter;
 			Image::Wrap wrap;
 		} settings;
+		
+		void drawv(const Matrix & t, const vertex * v) const;
 	};
 
 } // opengl