add textureTransform to ObjectBase

before textures load refactoring

shaders/ds_tonemap.glsl

@@ -20,6 +20,6 @@ void main(void) {
 	float g = gamma / frame_max;
 	res /= l;
 	l = 1 - exp(-l*g);
-	res *= l;
+	res = max(vec3(0.f), res * l);
 	qgl_FragColor = vec4(res, dot(res, luma));
 }