Cycles: Support sphere mapping for the image texture

intern/cycles/kernel/shaders/node_image_texture.osl

@@ -17,6 +17,25 @@
 #include "stdosl.h"
 #include "node_color.h"
 
+point map_to_sphere(vector dir)
+{
+	float len = length(dir);
+	float v, u;
+	if(len > 0.0) {
+		if(dir[0] == 0.0 && dir[1] == 0.0) {
+			u = 0.0;  /* othwise domain error */
+		}
+		else {
+			u = (1.0 - atan2(dir[0], dir[1]) / M_PI) / 2.0;
+		}
+		v = 1.0 - acos(dir[2] / len) / M_PI;
+	}
+	else {
+		v = u = 0.0; /* to avoid un-initialized variables */
+	}
+	return point(u, v, 0.0);
+}
+
 color image_texture_lookup(string filename, string color_space, float u, float v, output float Alpha, int use_alpha, int is_float, string interpolation)
 {
 	color rgb = (color)texture(filename, u, 1.0 - v, "wrap", "periodic", "interp", interpolation, "alpha", Alpha);
@@ -136,5 +155,10 @@ shader node_image_texture(
 			Alpha += weight[2] * tmp_alpha;
 		}
 	}
+	else if (projection == "Sphere") {
+		point projected = map_to_sphere((p - vector(0.5, 0.5, 0.5)) * 2.0);
+		Color = image_texture_lookup(filename, color_space,
+		                             projected[0], projected[1],
+		                             Alpha, use_alpha, is_float, interpolation);
+	}
 }
-

intern/cycles/kernel/svm/svm_image.h

@@ -363,6 +363,10 @@ ccl_device void svm_node_tex_image(KernelGlobals *kg, ShaderData *sd, float *sta
 
 	float3 co = stack_load_float3(stack, co_offset);
 	uint use_alpha = stack_valid(alpha_offset);
+	if(node.w == NODE_IMAGE_PROJ_SPHERE) {
+		co = (co - make_float3(0.5f, 0.5f, 0.5f)) * 2.0f;
+		map_to_sphere(&co.x, &co.y, co.x, co.y, co.z);
+	}
 	float4 f = svm_image_texture(kg, id, co.x, co.y, srgb, use_alpha);
 
 	if(stack_valid(out_offset))
@@ -463,7 +467,6 @@ ccl_device void svm_node_tex_image_box(KernelGlobals *kg, ShaderData *sd, float
 		stack_store_float(stack, alpha_offset, f.w);
 }
 
-
 ccl_device void svm_node_tex_environment(KernelGlobals *kg, ShaderData *sd, float *stack, uint4 node)
 {
 	uint id = node.y;

intern/cycles/kernel/svm/svm_types.h

@@ -334,6 +334,12 @@ typedef enum NodeNormalMapSpace {
 	NODE_NORMAL_MAP_BLENDER_WORLD,
 } NodeNormalMapSpace;
 
+typedef enum NodeImageProjection {
+	NODE_IMAGE_PROJ_FLAT   = 0,
+	NODE_IMAGE_PROJ_BOX    = 1,
+	NODE_IMAGE_PROJ_SPHERE = 2,
+} NodeImageProjection;
+
 typedef enum ShaderType {
 	SHADER_TYPE_SURFACE,
 	SHADER_TYPE_VOLUME,

intern/cycles/render/nodes.cpp

@@ -174,8 +174,9 @@ static ShaderEnum image_projection_init()
 {
 	ShaderEnum enm;
 
-	enm.insert("Flat", 0);
+	enm.insert("Flat", NODE_IMAGE_PROJ_FLAT);
-	enm.insert("Box", 1);
+	enm.insert("Box", NODE_IMAGE_PROJ_BOX);
+	enm.insert("Sphere", NODE_IMAGE_PROJ_SPHERE);
 
 	return enm;
 }
@@ -266,14 +267,15 @@ void ImageTextureNode::compile(SVMCompiler& compiler)
 			tex_mapping.compile(compiler, vector_in->stack_offset, vector_offset);
 		}
 
-		if(projection == "Flat") {
+		if(projection != "Box") {
 			compiler.add_node(NODE_TEX_IMAGE,
 				slot,
 				compiler.encode_uchar4(
 					vector_offset,
 					color_out->stack_offset,
 					alpha_out->stack_offset,
-					srgb));
+					srgb),
+				projection_enum[projection]);
 		}
 		else {
 			compiler.add_node(NODE_TEX_IMAGE_BOX,
@@ -285,7 +287,7 @@ void ImageTextureNode::compile(SVMCompiler& compiler)
 					srgb),
 				__float_as_int(projection_blend));
 		}
-	
+
 		if(vector_offset != vector_in->stack_offset)
 			compiler.stack_clear_offset(vector_in->type, vector_offset);
 	}

source/blender/makesdna/DNA_node_types.h

@@ -962,6 +962,7 @@ typedef struct NodeSunBeams {
 /* image texture */
 #define SHD_PROJ_FLAT				0
 #define SHD_PROJ_BOX				1
+#define SHD_PROJ_SPHERE				2
 
 /* image texture interpolation */
 #define SHD_INTERP_LINEAR		0

source/blender/makesrna/intern/rna_nodetree.c

@@ -3431,10 +3431,12 @@ static void def_sh_tex_image(StructRNA *srna)
 	};
 
 	static const EnumPropertyItem prop_projection_items[] = {
-		{SHD_PROJ_FLAT, "FLAT", 0, "Flat",
+		{SHD_PROJ_FLAT,   "FLAT", 0, "Flat",
-		                "Image is projected flat using the X and Y coordinates of the texture vector"},
+		                  "Image is projected flat using the X and Y coordinates of the texture vector"},
-		{SHD_PROJ_BOX,  "BOX", 0, "Box",
+		{SHD_PROJ_BOX,    "BOX", 0, "Box",
-		                "Image is projected using different components for each side of the object space bounding box"},
+		                  "Image is projected using different components for each side of the object space bounding box"},
+		{SHD_PROJ_SPHERE, "SPHERE", 0, "Sphere",
+		                  "Image is projected spherically using the Z axis as central"},
 		{0, NULL, 0, NULL, NULL}
 	};