Eevee: Planar Ref.: Invert view matrix to remove triangle front face flip

This was the cause of some issue with normal mapping. This way is cleaner
since it does not modify the state of the drawcalls and other ad-hoc
solutions to fix the problems down the road. Unfortunately, it does require
to fix every sampling coordinate for this texture.

Fix T62215: flipped normals in reflection plane

1 files changed, 2 insertions, 1 deletions

diff --git a/source/blender/draw/engines/eevee/shaders/lightprobe_lib.glsl b/source/blender/draw/engines/eevee/shaders/lightprobe_lib.glsl
index a991e640a79..7881079e258 100644
--- a/source/blender/draw/engines/eevee/shaders/lightprobe_lib.glsl
+++ b/source/blender/draw/engines/eevee/shaders/lightprobe_lib.glsl
@@ -200,7 +200,8 @@ vec3 probe_evaluate_planar(
 
 	/* TODO: If we support non-ssr planar reflection, we should blur them with gaussian
 	 * and chose the right mip depending on the cone footprint after projection */
-	vec3 sample = textureLod(probePlanars, vec3(refco.xy * 0.5 + 0.5, id), 0.0).rgb;
+	/* NOTE: X is inverted here to compensate inverted drawing.  */
+	vec3 sample = textureLod(probePlanars, vec3(refco.xy * vec2(-0.5, 0.5) + 0.5, id), 0.0).rgb;
 
 	return sample;
 }