PSP rendering and shader cleanup

src/extras/shaders/obj/scale_frag.inc

@@ -0,0 +1,21 @@
+const char *scale_frag_src =
+"uniform sampler2D tex0;\n"
+"uniform vec4 u_colorscale;\n"
+
+"FSIN vec4 v_color;\n"
+"FSIN vec2 v_tex0;\n"
+"FSIN float v_fog;\n"
+
+"void\n"
+"main(void)\n"
+"{\n"
+"	vec4 color;\n"
+"	color = v_color*texture(tex0, vec2(v_tex0.x, 1.0-v_tex0.y))*u_colorscale;\n"
+"	color.rgb = clamp(color.rgb, 0.0, 1.0);\n"
+"	color.rgb = mix(u_fogColor.rgb, color.rgb, v_fog);\n"
+"	DoAlphaTest(color.a);\n"
+
+"	FRAGCOLOR(color);\n"
+"}\n"
+
+;