Eevee: Fix geometry node for environments and support true_normal

Also minor cleanup for the Bump node.

source/blender/gpu/shaders/gpu_shader_material.glsl

@@ -1759,23 +1759,37 @@ void node_geometry(
         out vec3 true_normal, out vec3 incoming, out vec3 parametric,
         out float backfacing, out float pointiness)
 {
-	position = worldPosition;
-#ifndef VOLUMETRICS
-	normal = normalize(worldNormal);
-#else
-	normal = (toworld * vec4(N, 0.0)).xyz;
-#endif
-	tangent_orco_z(orco, orco);
-	node_tangent(N, orco, objmat, toworld, tangent);
-	true_normal = normal;
-
 	/* handle perspective/orthographic */
 	vec3 I_view = (ProjectionMatrix[3][3] == 0.0) ? normalize(I) : vec3(0.0, 0.0, -1.0);
 	incoming = -(toworld * vec4(I_view, 0.0)).xyz;
 
+#if defined(WORLD_BACKGROUND) || defined(PROBE_CAPTURE)
+	position = -incoming;
+	true_normal = normal = incoming;
+	tangent = parametric = vec3(0.0);
+	vec3(0.0);
+	backfacing = 0.0;
+	pointiness = 0.0;
+#else
+
+	position = worldPosition;
+#  ifndef VOLUMETRICS
+	normal = normalize(worldNormal);
+
+	vec3 B = dFdx(worldPosition);
+	vec3 T = dFdy(worldPosition);
+	true_normal = normalize(cross(B, T));
+#  else
+	normal = (toworld * vec4(N, 0.0)).xyz;
+	true_normal = normal;
+#  endif
+	tangent_orco_z(orco, orco);
+	node_tangent(N, orco, objmat, toworld, tangent);
+
 	parametric = vec3(barycentric, 0.0);
 	backfacing = (gl_FrontFacing) ? 0.0 : 1.0;
 	pointiness = 0.5;
+#endif
 }
 
 void generated_texco(vec3 I, vec3 attr_orco, out vec3 generated)
@@ -2930,9 +2944,9 @@ void node_normal_map(vec4 tangent, vec3 normal, vec3 texnormal, out vec3 outnorm
 
 void node_bump(float strength, float dist, float height, vec3 N, vec3 surf_pos, float invert, out vec3 result)
 {
-	if (invert != 0.0) {
-		dist *= -1.0;
-	}
+	N = mat3(ViewMatrix) * normalize(N);
+	dist *= invert;
+
 	vec3 dPdx = dFdx(surf_pos);
 	vec3 dPdy = dFdy(surf_pos);
 
@@ -2942,7 +2956,6 @@ void node_bump(float strength, float dist, float height, vec3 N, vec3 surf_pos,
 
 	/* Compute surface gradient and determinant. */
 	float det = dot(dPdx, Rx);
-	float absdet = abs(det);
 
 	float dHdx = dFdx(height);
 	float dHdy = dFdy(height);
@@ -2950,8 +2963,10 @@ void node_bump(float strength, float dist, float height, vec3 N, vec3 surf_pos,
 
 	strength = max(strength, 0.0);
 
-	result = normalize(absdet * N - dist * sign(det) * surfgrad);
-	result = normalize(strength * result + (1.0 - strength) * N);
+	result = normalize(abs(det) * N - dist * sign(det) * surfgrad);
+	result = normalize(mix(N, result, strength));
+
+	result = mat3(ViewMatrixInverse) * result;
 }
 
 void node_bevel(float radius, vec3 N, out vec3 result)

source/blender/nodes/shader/nodes/node_shader_bump.c

@@ -47,19 +47,13 @@ static bNodeSocketTemplate sh_node_bump_out[] = {
 
 static int gpu_shader_bump(GPUMaterial *mat, bNode *node, bNodeExecData *UNUSED(execdata), GPUNodeStack *in, GPUNodeStack *out)
 {
-	if (!in[3].link)
-		in[3].link = GPU_builtin(GPU_VIEW_NORMAL);
-	else
-		GPU_link(mat, "direction_transform_m4v3", in[3].link, GPU_builtin(GPU_VIEW_MATRIX), &in[3].link);
-	float invert = node->custom1;
-	GPU_stack_link(mat, node, "node_bump", in, out, GPU_builtin(GPU_VIEW_POSITION), GPU_constant(&invert));
-	/* Other nodes are applying view matrix if the input Normal has a link.
-	 * We don't want normal to have view matrix applied twice, so we cancel it here.
-	 *
-	 * TODO(sergey): This is an extra multiplication which cancels each other,
-	 * better avoid this but that requires bigger refactor.
-	 */
-	return GPU_link(mat, "direction_transform_m4v3", out[0].link, GPU_builtin(GPU_INVERSE_VIEW_MATRIX), &out[0].link);
+	if (!in[3].link) {
+		GPU_link(mat, "world_normals_get", &in[3].link);
+	}
+
+	float invert = (node->custom1) ? -1.0 : 1.0;
+
+	return GPU_stack_link(mat, node, "node_bump", in, out, GPU_builtin(GPU_VIEW_POSITION), GPU_constant(&invert));
 }
 
 /* node type definition */