diff options
Diffstat (limited to 'source/blender/gpu/shaders/compositor/compositor_symmetric_separable_blur.glsl')
-rw-r--r-- | source/blender/gpu/shaders/compositor/compositor_symmetric_separable_blur.glsl | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/source/blender/gpu/shaders/compositor/compositor_symmetric_separable_blur.glsl b/source/blender/gpu/shaders/compositor/compositor_symmetric_separable_blur.glsl new file mode 100644 index 00000000000..ab0c7baa787 --- /dev/null +++ b/source/blender/gpu/shaders/compositor/compositor_symmetric_separable_blur.glsl @@ -0,0 +1,53 @@ +#pragma BLENDER_REQUIRE(gpu_shader_compositor_blur_common.glsl) +#pragma BLENDER_REQUIRE(gpu_shader_compositor_texture_utilities.glsl) + +vec4 load_input(ivec2 texel) +{ + vec4 color; + if (extend_bounds) { + /* If bounds are extended, then we treat the input as padded by a radius amount of pixels. So + * we load the input with an offset by the radius amount and fallback to a transparent color if + * it is out of bounds. Notice that we subtract 1 because the weights texture have an extra + * center weight, see the SymmetricSeparableBlurWeights for more information. */ + int blur_size = texture_size(weights_tx) - 1; + color = texture_load(input_tx, texel - ivec2(blur_size, 0), vec4(0.0)); + } + else { + color = texture_load(input_tx, texel); + } + + if (gamma_correct_input) { + color = gamma_correct_blur_input(color); + } + + return color; +} + +void main() +{ + ivec2 texel = ivec2(gl_GlobalInvocationID.xy); + + vec4 accumulated_color = vec4(0.0); + + /* First, compute the contribution of the center pixel. */ + vec4 center_color = load_input(texel); + accumulated_color += center_color * texture_load(weights_tx, 0).x; + + /* Then, compute the contributions of the pixel to the right and left, noting that the + * weights texture only stores the weights for the positive half, but since the filter is + * symmetric, the same weight is used for the negative half and we add both of their + * contributions. */ + for (int i = 1; i < texture_size(weights_tx); i++) { + float weight = texture_load(weights_tx, i).x; + accumulated_color += load_input(texel + ivec2(i, 0)) * weight; + accumulated_color += load_input(texel + ivec2(-i, 0)) * weight; + } + + if (gamma_uncorrect_output) { + accumulated_color = gamma_uncorrect_blur_output(accumulated_color); + } + + /* Write the color using the transposed texel. See the execute_separable_blur_horizontal_pass + * method for more information on the rational behind this. */ + imageStore(output_img, texel.yx, accumulated_color); +} |