devicePixelRatio() support

shaders/ds_geom.glsl

@@ -32,6 +32,10 @@ void main(void) {
 
 	vec4 diffuse = qgl_materialTexture(QGL_MAP_DIFFUSE, tc, vec4(0)) * object_color;
 	diffuse.rgb *= qgl_material[qgl_MaterialIndex].color_diffuse.rgb;
+#ifdef SOLID
+	if(diffuse.a < 0.5)
+		discard;
+#endif
 	diffuse.a *= (1.f - qgl_material[qgl_MaterialIndex].transparency);
 
 	vec3 normal, dn;