diff --git a/basic.glsl b/basic.glsl
new file mode 100644
index 0000000..6679aa5
--- /dev/null
+++ b/basic.glsl
@@ -0,0 +1,22 @@
+#define COMPAT_PRECISION
+
+varying vec2 TEX0;
+
+#if defined(VERTEX)
+
+void main()
+{
+	TEX0 = gl_MultiTexCoord0.st; //vec2(gl_MultiTexCoord0.x, 1.0-gl_MultiTexCoord0.y)*1.0001;
+	gl_Position = gl_ModelViewProjectionMatrix * gl_Vertex;
+}
+
+#elif defined(FRAGMENT)
+
+uniform sampler2D Texture;
+
+void main()
+{
+    gl_FragColor = vec4(TEX0.s, TEX0.t, 0, 1); texture2D(Texture, TEX0);
+}
+
+#endif
diff --git a/main.cpp b/main.cpp
index 8b774bc..6da655d 100644
--- a/main.cpp
+++ b/main.cpp
@@ -18,13 +18,14 @@ int main(int argc, char **argv)
 	printf("VIDEO DRIVERS AVAILABLE:\n");
 	for (int i=0; i<num_drivers;++i) printf("%i: %s\n", i, SDL_GetVideoDriver(i));
 
+	SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_COMPATIBILITY);
 	SDL_SetHint(SDL_HINT_RENDER_DRIVER, "opengl");
 	SDL_Renderer *renderer = SDL_CreateRenderer(win, NULL); //-1, SDL_RENDERER_ACCELERATED | SDL_RENDERER_TARGETTEXTURE);
 	if (!renderer) { printf("ERROR al crear el renderer: %s\n", SDL_GetError()); }
 	SDL_Texture *texTarget = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_ARGB8888, SDL_TEXTUREACCESS_TARGET, WIDTH, HEIGHT);
 	if (!win) { printf("ERROR al crear la textura target: %s\n", SDL_GetError()); }
 
-	std::ifstream f("crtpi.glsl");
+	std::ifstream f("basic.glsl");
 	std::string source((std::istreambuf_iterator<char>(f)), std::istreambuf_iterator<char>());
 
 	shader::init(win, texTarget, source.c_str());