luboslenco
46 lines
1.3 KiB
GLSL
46 lines
1.3 KiB
GLSL
#version 450
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uniform sampler2D tex;
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uniform vec2 screen_size_inv;
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uniform int current_mip_level;
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in vec2 tex_coord;
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out vec4 frag_color;
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const float bloom_knee = 0.5;
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const float bloom_threshold = 0.8;
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const float epsilon = 6.2e-5;
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vec3 downsample_dual_filter(const sampler2D tex, const vec2 tex_coord, const vec2 texel_size) {
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vec3 delta = texel_size.xyx * vec3(0.5, 0.5, -0.5);
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vec3 result;
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result = textureLod(tex, tex_coord, 0.0).rgb * 4.0;
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result += textureLod(tex, tex_coord - delta.xy, 0.0).rgb;
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result += textureLod(tex, tex_coord - delta.zy, 0.0).rgb;
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result += textureLod(tex, tex_coord + delta.zy, 0.0).rgb;
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result += textureLod(tex, tex_coord + delta.xy, 0.0).rgb;
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return result * (1.0 / 8.0);
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}
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void main() {
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frag_color.rgb = downsample_dual_filter(tex, tex_coord, screen_size_inv);
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if (current_mip_level == 0) {
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float brightness = max(frag_color.r, max(frag_color.g, frag_color.b));
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float softening_curve = brightness - bloom_threshold + bloom_knee;
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softening_curve = clamp(softening_curve, 0.0, 2.0 * bloom_knee);
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softening_curve = softening_curve * softening_curve / (4 * bloom_knee + epsilon);
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float contribution_factor = max(softening_curve, brightness - bloom_threshold);
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contribution_factor /= max(epsilon, brightness);
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frag_color.rgb *= contribution_factor;
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}
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frag_color.a = 1.0;
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}
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