diff options
Diffstat (limited to 'source/blender/draw/engines/overlay/shaders/armature_sphere_solid_frag.glsl')
-rw-r--r-- | source/blender/draw/engines/overlay/shaders/armature_sphere_solid_frag.glsl | 76 |
1 files changed, 76 insertions, 0 deletions
diff --git a/source/blender/draw/engines/overlay/shaders/armature_sphere_solid_frag.glsl b/source/blender/draw/engines/overlay/shaders/armature_sphere_solid_frag.glsl new file mode 100644 index 00000000000..94f339c4561 --- /dev/null +++ b/source/blender/draw/engines/overlay/shaders/armature_sphere_solid_frag.glsl @@ -0,0 +1,76 @@ + +uniform float alpha = 0.4; + +flat in vec3 finalStateColor; +flat in vec3 finalBoneColor; +flat in mat4 sphereMatrix; +in vec3 viewPosition; + +#ifdef GL_ARB_conservative_depth +/* Saves a lot of overdraw! */ +layout(depth_greater) out float gl_FragDepth; +#endif + +out vec4 fragColor; + +#define cameraPos ViewMatrixInverse[3].xyz + +float get_depth_from_view_z(float z) +{ + if (ProjectionMatrix[3][3] == 0.0) { + z = (-ProjectionMatrix[3][2] / z) - ProjectionMatrix[2][2]; + } + else { + z = z * ProjectionMatrix[2][2] / (1.0 - ProjectionMatrix[3][2]); + } + return z * 0.5 + 0.5; +} + +void main() +{ + const float sphere_radius = 0.05; + + bool is_perp = (ProjectionMatrix[3][3] == 0.0); + vec3 ray_ori_view = (is_perp) ? vec3(0.0) : viewPosition.xyz; + vec3 ray_dir_view = (is_perp) ? viewPosition : vec3(0.0, 0.0, -1.0); + + /* Single matrix mul without branch. */ + vec4 mul_vec = (is_perp) ? vec4(ray_dir_view, 0.0) : vec4(ray_ori_view, 1.0); + vec3 mul_res = (sphereMatrix * mul_vec).xyz; + + /* Reminder : + * sphereMatrix[3] is the view space origin in sphere space (sph_ori -> view_ori). + * sphereMatrix[2] is the view space Z axis in sphere space. */ + + /* convert to sphere local space */ + vec3 ray_ori = (is_perp) ? sphereMatrix[3].xyz : mul_res; + vec3 ray_dir = (is_perp) ? mul_res : -sphereMatrix[2].xyz; + float ray_len = length(ray_dir); + ray_dir /= ray_len; + + /* Line to sphere intersect */ + const float sphere_radius_sqr = sphere_radius * sphere_radius; + float b = dot(ray_ori, ray_dir); + float c = dot(ray_ori, ray_ori) - sphere_radius_sqr; + float h = b * b - c; + float t = -sqrt(max(0.0, h)) - b; + + /* Compute dot product for lighting */ + vec3 p = ray_dir * t + ray_ori; /* Point on sphere */ + vec3 n = normalize(p); /* Normal is just the point in sphere space, normalized. */ + vec3 l = normalize(sphereMatrix[2].xyz); /* Just the view Z axis in the sphere space. */ + + /* Smooth lighting factor. */ + const float s = 0.2; /* [0.0-0.5] range */ + float fac = clamp((dot(n, l) * (1.0 - s)) + s, 0.0, 1.0); + fragColor.rgb = mix(finalStateColor, finalBoneColor, fac); + + /* 2x2 dither pattern to smooth the lighting. */ + float dither = (0.5 + dot(vec2(ivec2(gl_FragCoord.xy) & ivec2(1)), vec2(1.0, 2.0))) * 0.25; + dither *= (1.0 / 255.0); /* Assume 8bit per color buffer. */ + + fragColor = vec4(fragColor.rgb + dither, alpha); + + t /= ray_len; + gl_FragDepth = get_depth_from_view_z(ray_dir_view.z * t + ray_ori_view.z); +} |