Eevee: Ssr: Add ssr id to glossy nodes.

An id is given to each glossy node in order to determine which specular lobe is using ssr.

4 files changed, 48 insertions, 4 deletions

diff --git a/source/blender/nodes/shader/node_shader_tree.c b/source/blender/nodes/shader/node_shader_tree.c
index b5d77e99328..52e9ed35a2e 100644
--- a/source/blender/nodes/shader/node_shader_tree.c
+++ b/source/blender/nodes/shader/node_shader_tree.c
@@ -475,6 +475,48 @@ static void ntree_shader_relink_displacement(bNodeTree *ntree,
 	ntreeUpdateTree(G.main, ntree);
 }
 
+static bool ntree_tag_ssr_bsdf_cb(bNode *fromnode, bNode *UNUSED(tonode), void *userdata, const bool UNUSED(reversed))
+{
+	switch (fromnode->type) {
+		case SH_NODE_BSDF_ANISOTROPIC:
+		case SH_NODE_EEVEE_METALLIC:
+		case SH_NODE_EEVEE_SPECULAR:
+		case SH_NODE_BSDF_PRINCIPLED:
+		case SH_NODE_BSDF_GLOSSY:
+			fromnode->ssr_id = (*(float *)userdata);
+			(*(float *)userdata) += 1;
+			break;
+		default:
+			/* We could return false here but since we (will)
+			 * allow the use of Closure as RGBA, we can have
+			 * Bsdf nodes linked to other Bsdf nodes. */
+			break;
+	}
+
+	return true;
+}
+
+/* EEVEE: Scan the ntree to set the Screen Space Reflection
+ * layer id of every specular node.
+ */
+static void ntree_shader_tag_ssr_node(bNodeTree *ntree, short compatibility)
+{
+	if (compatibility != NODE_NEWER_SHADING) {
+		/* We can only deal with new shading system here. */
+		return;
+	}
+
+	bNode *output_node = ntree_shader_output_node(ntree);
+	if (output_node == NULL) {
+		return;
+	}
+	/* Make sure sockets links pointers are correct. */
+	ntreeUpdateTree(G.main, ntree);
+
+	int lobe_count = 0;
+	nodeChainIter(ntree, output_node, ntree_tag_ssr_bsdf_cb, &lobe_count, true);
+}
+
 void ntreeGPUMaterialNodes(bNodeTree *ntree, GPUMaterial *mat, short compatibility)
 {
 	/* localize tree to create links for reroute and mute */
@@ -486,6 +528,8 @@ void ntreeGPUMaterialNodes(bNodeTree *ntree, GPUMaterial *mat, short compatibili
 	 */
 	ntree_shader_relink_displacement(localtree, compatibility);
 
+	ntree_shader_tag_ssr_node(localtree, compatibility);
+
 	exec = ntreeShaderBeginExecTree(localtree);
 	ntreeExecGPUNodes(exec, mat, 1, compatibility);
 	ntreeShaderEndExecTree(exec);
diff --git a/source/blender/nodes/shader/nodes/node_shader_bsdf_principled.c b/source/blender/nodes/shader/nodes/node_shader_bsdf_principled.c
index 4ae0474d685..1ec77bc9189 100644
--- a/source/blender/nodes/shader/nodes/node_shader_bsdf_principled.c
+++ b/source/blender/nodes/shader/nodes/node_shader_bsdf_principled.c
@@ -100,10 +100,10 @@ static int node_shader_gpu_bsdf_principled(GPUMaterial *mat, bNode *node, bNodeE
 
 	/* Only use complex versions when needed. */
 	if (!in[12].link && (in[12].vec[0] == 0.0f)) {
-		return GPU_stack_link(mat, node, "node_bsdf_principled_simple", in, out, GPU_builtin(GPU_VIEW_POSITION));
+		return GPU_stack_link(mat, node, "node_bsdf_principled_simple", in, out, GPU_builtin(GPU_VIEW_POSITION), GPU_uniform(&node->ssr_id));
 	}
 	else {
-		return GPU_stack_link(mat, node, "node_bsdf_principled_clearcoat", in, out, GPU_builtin(GPU_VIEW_POSITION));
+		return GPU_stack_link(mat, node, "node_bsdf_principled_clearcoat", in, out, GPU_builtin(GPU_VIEW_POSITION), GPU_uniform(&node->ssr_id));
 	}
 }
 
diff --git a/source/blender/nodes/shader/nodes/node_shader_eevee_metallic.c b/source/blender/nodes/shader/nodes/node_shader_eevee_metallic.c
index 2a8a3a44f39..071486493fa 100644
--- a/source/blender/nodes/shader/nodes/node_shader_eevee_metallic.c
+++ b/source/blender/nodes/shader/nodes/node_shader_eevee_metallic.c
@@ -68,7 +68,7 @@ static int node_shader_gpu_eevee_metallic(GPUMaterial *mat, bNode *node, bNodeEx
 		GPU_link(mat, "set_value", GPU_uniform(&one), &in[10].link);
 	}
 
-	return GPU_stack_link(mat, node, "node_eevee_metallic", in, out);
+	return GPU_stack_link(mat, node, "node_eevee_metallic", in, out, GPU_uniform(&node->ssr_id));
 }
 
 
diff --git a/source/blender/nodes/shader/nodes/node_shader_eevee_specular.c b/source/blender/nodes/shader/nodes/node_shader_eevee_specular.c
index 954f9b3ee4a..c249e77c17a 100644
--- a/source/blender/nodes/shader/nodes/node_shader_eevee_specular.c
+++ b/source/blender/nodes/shader/nodes/node_shader_eevee_specular.c
@@ -67,7 +67,7 @@ static int node_shader_gpu_eevee_specular(GPUMaterial *mat, bNode *node, bNodeEx
 		GPU_link(mat, "set_value", GPU_uniform(&one), &in[9].link);
 	}
 
-	return GPU_stack_link(mat, node, "node_eevee_specular", in, out);
+	return GPU_stack_link(mat, node, "node_eevee_specular", in, out, GPU_uniform(&node->ssr_id));
 }