-#define GL_GLEXT_PROTOTYPES 1
-
#include <math.h>
-#include <GL/gl.h>
-#include <GL/glext.h>
#include <assert.h>
#include "blur_effect.h"
#include "util.h"
+#include "opengl.h"
// Must match blur_effect.frag.
#define NUM_TAPS 16
-BlurEffect::BlurEffect() {
+BlurEffect::BlurEffect()
+ : radius(3.0f)
+{
hpass = new SingleBlurPassEffect();
hpass->set_int("direction", SingleBlurPassEffect::HORIZONTAL);
vpass = new SingleBlurPassEffect();
vpass->set_int("direction", SingleBlurPassEffect::VERTICAL);
+
+ update_radius();
}
-void BlurEffect::add_self_to_effect_chain(EffectChain *chain, const std::vector<Effect *> &inputs) {
+void BlurEffect::add_self_to_effect_chain(EffectChain *chain, const std::vector<Effect *> &inputs)
+{
assert(inputs.size() == 1);
hpass->add_self_to_effect_chain(chain, inputs);
std::vector<Effect *> vpass_inputs;
vpass_inputs.push_back(hpass);
- vpass->add_self_to_effect_chain(chain, vpass_inputs);
+ vpass->add_self_to_effect_chain(chain, vpass_inputs);
+}
+
+void BlurEffect::update_radius()
+{
+ // We only have 16 taps to work with on each side, and we want that to
+ // reach out to about 2.5*sigma. Bump up the mipmap levels (giving us
+ // box blurs) until we have what we need.
+ //
+ // TODO: Consider the actual width and height (they influence mipmap
+ // sizes subtly).
+ unsigned base_mipmap_level = 0;
+ float adjusted_radius = radius;
+ while (adjusted_radius * 1.5f > NUM_TAPS / 2) {
+ ++base_mipmap_level;
+ adjusted_radius /= 2.0f;
+ }
+
+ bool ok = hpass->set_float("radius", adjusted_radius);
+ ok |= hpass->set_int("width", 1280 / (1 << base_mipmap_level)); // FIXME
+ ok |= hpass->set_int("height", 720 / (1 << base_mipmap_level)); // FIXME
+
+ ok |= vpass->set_float("radius", adjusted_radius);
+ ok |= vpass->set_int("width", 1280 / (1 << base_mipmap_level)); // FIXME
+ ok |= vpass->set_int("height", 720 / (1 << base_mipmap_level)); // FIXME
+
+ assert(ok);
}
bool BlurEffect::set_float(const std::string &key, float value) {
- if (!hpass->set_float(key, value)) {
- return false;
+ if (key == "radius") {
+ radius = value;
+ update_radius();
+ return true;
}
- return vpass->set_float(key, value);
+ return false;
}
SingleBlurPassEffect::SingleBlurPassEffect()
: radius(3.0f),
- direction(HORIZONTAL)
+ direction(HORIZONTAL),
+ width(1280),
+ height(720)
{
- register_float("radius", (float *)&radius);
+ register_float("radius", &radius);
register_int("direction", (int *)&direction);
+ register_int("width", &width);
+ register_int("height", &height);
}
std::string SingleBlurPassEffect::output_fragment_shader()
return read_file("blur_effect.frag");
}
-void SingleBlurPassEffect::set_uniforms(GLuint glsl_program_num, const std::string &prefix, unsigned *sampler_num)
+void SingleBlurPassEffect::set_gl_state(GLuint glsl_program_num, const std::string &prefix, unsigned *sampler_num)
{
- Effect::set_uniforms(glsl_program_num, prefix, sampler_num);
-
- int base_texture_size, texture_size;
- if (direction == HORIZONTAL) {
- base_texture_size = texture_size = 1280; // FIXME
- } else if (direction == VERTICAL) {
- base_texture_size = texture_size = 720; // FIXME
- } else {
- assert(false);
- }
-
- // We only have 16 taps to work with on each side, and we want that to
- // reach out to about 2.5*sigma. Bump up the mipmap levels (giving us
- // box blurs) until we have what we need.
- //
- // FIXME: we really need to pick the same mipmap level for both horizontal and vertical!
- unsigned base_mipmap_level = 0;
- float adjusted_radius = radius;
- while (texture_size > 1 && adjusted_radius * 2.5f > NUM_TAPS / 2) {
- ++base_mipmap_level;
- texture_size /= 2; // Rounding down.
- adjusted_radius = radius * float(texture_size) / float(base_texture_size);
- }
-
- // In the second pass, we do the same, but don't sample from a mipmap;
- // that would re-blur the other direction in an ugly fashion, and we already
- // have the vertical box blur we need from that pass.
- //
- // TODO: We really need to present horizontal+vertical as a unit;
- // currently, there's really no guarantee vertical blur is the second pass.
- if (direction == VERTICAL) {
- base_mipmap_level = 0;
- }
-
- glActiveTexture(GL_TEXTURE0);
- check_error();
- glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_BASE_LEVEL, base_mipmap_level);
- check_error();
- glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAX_LEVEL, base_mipmap_level);
- check_error();
+ Effect::set_gl_state(glsl_program_num, prefix, sampler_num);
// Compute the weights; they will be symmetrical, so we only compute
// the right side.
} else {
float sum = 0.0f;
for (unsigned i = 0; i < NUM_TAPS + 1; ++i) {
- float z = i / adjusted_radius;
+ float z = i / radius;
// Gaussian blur is a common, but maybe not the prettiest choice;
// it can feel a bit too blurry in the fine detail and too little
}
}
-#if 0
- // NOTE: This is currently broken.
-
// Since the GPU gives us bilinear sampling for free, we can get two
// samples for the price of one (for every but the center sample,
// in which case this trick doesn't buy us anything). Simply sample
offset = w2 / (w1 + w2);
total_weight = w1 + w2;
}
-#if 0
- // hack for easier visualization
- offset = 0.5f;
- total_weight = 8.0f;
-#endif
float x = 0.0f, y = 0.0f;
if (direction == HORIZONTAL) {
- x = (base_pos + offset) / (float)texture_size;
+ x = (base_pos + offset) / (float)width;
} else if (direction == VERTICAL) {
- y = (base_pos + offset) / (float)texture_size;
+ y = (base_pos + offset) / (float)height;
} else {
assert(false);
}
}
set_uniform_vec4_array(glsl_program_num, prefix, "samples", samples, NUM_TAPS / 2 + 1);
-#else
- // Boring, at-whole-pixels sampling.
- float samples[4 * NUM_TAPS];
-
- // All other samples.
- for (unsigned i = 0; i < NUM_TAPS + 1; ++i) {
- float x = 0.0f, y = 0.0f;
-
- if (direction == HORIZONTAL) {
- x = i / (float)texture_size;
- } else if (direction == VERTICAL) {
- y = i / (float)texture_size;
- } else {
- assert(false);
- }
-
- samples[4 * i + 0] = x;
- samples[4 * i + 1] = y;
- samples[4 * i + 2] = weight[i];
- samples[4 * i + 3] = 0.0f;
- }
+}
- set_uniform_vec4_array(glsl_program_num, prefix, "samples", samples, NUM_TAPS + 1);
-#endif
+void SingleBlurPassEffect::clear_gl_state()
+{
}