patch TinyRenderer so it software-renders in an OpenGL texture, for testing

fix texture support: flip texture to make OpenGL happy (lower-left is origin)
add path prefix to .obj loader, so materials/textures are loaded ok.

examples/TinyRenderer/TinyRenderer.h

@@ -0,0 +1,39 @@
+#ifndef TINY_RENDERER_H
+#define TINY_RENDERER_H
+
+//#include "TinyRenderer/our_gl.h"
+#include "TinyRenderer/geometry.h"
+#include "Bullet3Common/b3AlignedObjectArray.h"
+#include "TinyRenderer/tgaimage.h"
+
+struct TinyRenderObjectData
+{
+    //Camera
+    Matrix m_viewMatrix;
+    Matrix m_projectionMatrix;
+    Matrix m_viewportMatrix;
+
+    //Model (vertices, indices, textures, shader)
+    Matrix m_modelMatrix;    
+    class Model*  m_model;
+    //class IShader* m_shader; todo(erwincoumans) expose the shader, for now we use a default shader
+            
+    //Output
+    int m_width;
+    int m_height;
+    TGAImage m_rgbColorBuffer;
+    b3AlignedObjectArray<float> m_depthBuffer;
+    
+    TinyRenderObjectData(int width, int height, const char* objFileName);
+    virtual ~TinyRenderObjectData();
+    
+};
+
+
+class TinyRenderer
+{
+    public:
+        static void renderObject(TinyRenderObjectData& renderData);
+};
+
+#endif // TINY_RENDERER_Hbla