1 #define GL_GLEXT_PROTOTYPES 1
7 #include "blur_effect.h"
10 BlurEffect::BlurEffect()
13 register_float("radius", (float *)&radius);
16 std::string BlurEffect::output_fragment_shader()
18 return read_file("blur_effect.frag");
21 void BlurEffect::set_uniforms(GLuint glsl_program_num, const std::string &prefix, unsigned *sampler_num)
23 Effect::set_uniforms(glsl_program_num, prefix, sampler_num);
25 // We only have 15 taps to work with, and we want that to reach out to about 2.5*sigma.
26 // Bump up the mipmap levels (giving us box blurs) until we have what we need.
27 unsigned base_mipmap_level = 0;
28 float adjusted_radius = radius;
29 float pixel_size = 1.0f;
30 while (adjusted_radius * 2.5f > 7.0f) {
32 adjusted_radius *= 0.5f;
36 glActiveTexture(GL_TEXTURE0);
37 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_BASE_LEVEL, base_mipmap_level);
40 set_uniform_float(glsl_program_num, prefix, "pixel_offset", pixel_size / 1280.0f); // FIXME
42 // Simple Gaussian weights for now.
43 float weight[15], total = 0.0f;
44 for (unsigned i = 0; i < 15; ++i) {
45 float z = (i - 7.0f) / adjusted_radius;
46 weight[i] = exp(-(z*z));
49 printf("[mip level %d] ", base_mipmap_level);
50 for (unsigned i = 0; i < 15; ++i) {
52 printf("%f ", weight[i]);
55 set_uniform_float_array(glsl_program_num, prefix, "weight", weight, 15);