Support all Cycles image texture projections in the GLSL viewport
authorRalf Hölzemer <r.hoelzemer@googlemail.com>
Mon, 30 May 2016 08:23:43 +0000 (10:23 +0200)
committerSergey Sharybin <sergey.vfx@gmail.com>
Mon, 30 May 2016 08:29:46 +0000 (10:29 +0200)
This patch enables Tube, Sphere and Box projections in GLSL for the image texture node.

Reviewers: sergey

Projects: #nodes, #opengl_gfx

Differential Revision: https://developer.blender.org/D2036

source/blender/gpu/shaders/gpu_shader_material.glsl
source/blender/nodes/shader/nodes/node_shader_tex_image.c

index 84806e9f09604a4370ca6fd30693526c7b3bdf55..a3b058030638eb0af1813e71499aeb06555b2ab7 100644 (file)
@@ -218,6 +218,42 @@ void point_transform_m4v3(vec3 vin, mat4 mat, out vec3 vout)
        vout = (mat * vec4(vin, 1.0)).xyz;
 }
 
+void point_texco_remap_square(vec3 vin, out vec3 vout)
+{
+       vout = vec3(vin - vec3(0.5, 0.5, 0.5)) * 2.0;
+}
+
+void point_map_to_sphere(vec3 vin, out vec3 vout)
+{
+       float len = length(vin);
+       float v, u;
+       if (len > 0.0) {
+               if (vin.x == 0.0 && vin.y == 0.0)
+                       u = 0.0;
+               else
+                       u = (1.0 - atan(vin.x, vin.y) / M_PI) / 2.0;
+
+               v = 1.0 - acos(vin.z / len) / M_PI;
+       }
+       else
+               v = u = 0.0;
+
+       vout = vec3(u, v, 0.0);
+}
+
+void point_map_to_tube(vec3 vin, out vec3 vout)
+{
+       float u, v;
+       v = (vin.z + 1.0) * 0.5;
+       float len = sqrt(vin.x * vin.x + vin.y * vin[1]);
+       if (len > 0.0)
+               u = (1.0 - (atan(vin.x / len, vin.y / len) / M_PI)) * 0.5;
+       else
+               v = u = 0.0;
+
+       vout = vec3(u, v, 0.0);
+}
+
 void mapping(vec3 vec, mat4 mat, vec3 minvec, vec3 maxvec, float domin, float domax, out vec3 outvec)
 {
        outvec = (mat * vec4(vec, 1.0)).xyz;
@@ -2872,6 +2908,82 @@ void node_tex_image(vec3 co, sampler2D ima, out vec4 color, out float alpha)
        alpha = color.a;
 }
 
+void node_tex_image_box(vec3 texco,
+                        vec3 nob,
+                        sampler2D ima,
+                        float blend,
+                        out vec4 color,
+                        out float alpha)
+{
+       /* project from direction vector to barycentric coordinates in triangles */
+       nob = vec3(abs(nob.x), abs(nob.y), abs(nob.z));
+       nob /= (nob.x + nob.y + nob.z);
+
+       /* basic idea is to think of this as a triangle, each corner representing
+        * one of the 3 faces of the cube. in the corners we have single textures,
+        * in between we blend between two textures, and in the middle we a blend
+        * between three textures.
+        *
+        * the Nxyz values are the barycentric coordinates in an equilateral
+        * triangle, which in case of blending, in the middle has a smaller
+        * equilateral triangle where 3 textures blend. this divides things into
+        * 7 zones, with an if () test for each zone */
+
+       vec3 weight = vec3(0.0, 0.0, 0.0);
+       float limit = 0.5 * (1.0 + blend);
+
+       /* first test for corners with single texture */
+       if (nob.x > limit * (nob.x + nob.y) && nob.x > limit * (nob.x + nob.z)) {
+               weight.x = 1.0;
+       }
+       else if (nob.y > limit * (nob.x + nob.y) && nob.y > limit * (nob.y + nob.z)) {
+               weight.y = 1.0;
+       }
+       else if (nob.z > limit * (nob.x + nob.z) && nob.z > limit * (nob.y + nob.z)) {
+               weight.z = 1.0;
+       }
+       else if (blend > 0.0) {
+               /* in case of blending, test for mixes between two textures */
+               if (nob.z < (1.0 - limit) * (nob.y + nob.x)) {
+                       weight.x = nob.x / (nob.x + nob.y);
+                       weight.x = clamp((weight.x - 0.5 * (1.0 - blend)) / blend, 0.0, 1.0);
+                       weight.y = 1.0 - weight.x;
+               }
+               else if (nob.x < (1.0 - limit) * (nob.y + nob.z)) {
+                       weight.y = nob.y / (nob.y + nob.z);
+                       weight.y = clamp((weight.y - 0.5 * (1.0 - blend)) / blend, 0.0, 1.0);
+                       weight.z = 1.0 - weight.y;
+               }
+               else if (nob.y < (1.0 - limit) * (nob.x + nob.z)) {
+                       weight.x = nob.x / (nob.x + nob.z);
+                       weight.x = clamp((weight.x - 0.5 * (1.0 - blend)) / blend, 0.0, 1.0);
+                       weight.z = 1.0 - weight.x;
+               }
+               else {
+                       /* last case, we have a mix between three */
+                       weight.x = ((2.0 - limit) * nob.x + (limit - 1.0)) / (2.0 * limit - 1.0);
+                       weight.y = ((2.0 - limit) * nob.y + (limit - 1.0)) / (2.0 * limit - 1.0);
+                       weight.z = ((2.0 - limit) * nob.z + (limit - 1.0)) / (2.0 * limit - 1.0);
+               }
+       }
+       else {
+               /* Desperate mode, no valid choice anyway, fallback to one side.*/
+               weight.x = 1.0;
+       }
+
+       if (weight.x > 0.0) {
+               color += weight.x * texture2D(ima, texco.yz);
+       }
+       if (weight.y > 0.0) {
+               color += weight.y * texture2D(ima, texco.xz);
+       }
+       if (weight.z > 0.0) {
+               color += weight.z * texture2D(ima, texco.yx);
+       }
+
+       alpha = color.a;
+}
+
 void node_tex_image_empty(vec3 co, out vec4 color, out float alpha)
 {
        color = vec4(0.0);
index f0a8cda045e89f6e995f4c3e2851ee5bfff0bbc4..71200dfe9d3e23a1e595f50a516f7263f3fe53cd 100644 (file)
@@ -59,17 +59,49 @@ static int node_shader_gpu_tex_image(GPUMaterial *mat, bNode *node, bNodeExecDat
        Image *ima = (Image *)node->id;
        ImageUser *iuser = NULL;
        NodeTexImage *tex = node->storage;
+
+       GPUNodeLink *norm;
+
        int isdata = tex->color_space == SHD_COLORSPACE_NONE;
+       float blend = tex->projection_blend;
 
        if (!ima)
                return GPU_stack_link(mat, "node_tex_image_empty", in, out);
-       
+
        if (!in[0].link)
                in[0].link = GPU_attribute(CD_MTFACE, "");
 
        node_shader_gpu_tex_mapping(mat, node, in, out);
 
-       GPU_stack_link(mat, "node_tex_image", in, out, GPU_image(ima, iuser, isdata));
+       switch (tex->projection) {
+               case SHD_PROJ_FLAT:
+                       GPU_stack_link(mat, "node_tex_image", in, out, GPU_image(ima, iuser, isdata));
+                       break;
+               case SHD_PROJ_BOX:
+                       GPU_link(mat, "direction_transform_m4v3", GPU_builtin(GPU_VIEW_NORMAL),
+                                                                 GPU_builtin(GPU_INVERSE_VIEW_MATRIX),
+                                                                 &norm);
+                       GPU_link(mat, "direction_transform_m4v3", norm,
+                                                                 GPU_builtin(GPU_INVERSE_OBJECT_MATRIX),
+                                                                 &norm);
+                       GPU_link(mat, "node_tex_image_box", in[0].link,
+                                                           norm,
+                                                           GPU_image(ima, iuser, isdata),
+                                                           GPU_uniform(&blend),
+                                                           &out[0].link,
+                                                           &out[1].link);
+                       break;
+               case SHD_PROJ_SPHERE:
+                       GPU_link(mat, "point_texco_remap_square", in[0].link, &in[0].link);
+                       GPU_link(mat, "point_map_to_sphere", in[0].link, &in[0].link);
+                       GPU_stack_link(mat, "node_tex_image", in, out, GPU_image(ima, iuser, isdata));
+                       break;
+               case SHD_PROJ_TUBE:
+                       GPU_link(mat, "point_texco_remap_square", in[0].link, &in[0].link);
+                       GPU_link(mat, "point_map_to_tube", in[0].link, &in[0].link);
+                       GPU_stack_link(mat, "node_tex_image", in, out, GPU_image(ima, iuser, isdata));
+                       break;
+       }
 
        ImBuf *ibuf = BKE_image_acquire_ibuf(ima, iuser, NULL);
        if ((tex->color_space == SHD_COLORSPACE_COLOR) &&