env map rendering

src/extras/shaders/leedsVehicle_blend.frag

@@ -0,0 +1,32 @@
+uniform sampler2D tex0;
+uniform sampler2D tex1;
+
+uniform float u_fxparams;
+
+#define shininess (u_fxparams)
+
+FSIN vec4 v_color;
+FSIN vec2 v_tex0;
+FSIN vec2 v_tex1;
+FSIN float v_fog;
+
+void
+main(void)
+{
+	vec4 pass1 = v_color*texture(tex0, vec2(v_tex0.x, 1.0-v_tex0.y));
+	vec4 pass2 = texture(tex1, vec2(v_tex1.x, 1.0-v_tex1.y));
+	pass2.a *= shininess;
+
+	pass1.rgb = mix(u_fogColor.rgb, pass1.rgb, v_fog);
+	pass2.rgb = mix(vec3(0.0, 0.0, 0.0), pass2.rgb, v_fog);
+
+	// We simulate drawing this in two passes.
+	// We premultiply alpha so render state should be one.
+	vec4 color;
+	color.rgb = pass1.rgb*pass1.a*(1.0-pass2.a) + pass2.rgb*pass2.a;
+	color.a = pass1.a*(1.0-pass2.a) + pass2.a;
+
+	DoAlphaTest(color.a);
+
+	FRAGCOLOR(color);
+}