#include "effect_util.h"
#include "util.h"
-// Must match blur_effect.frag.
-#define NUM_TAPS 16
-
using namespace std;
namespace movit {
BlurEffect::BlurEffect()
- : radius(3.0f),
+ : num_taps(16),
+ radius(3.0f),
input_width(1280),
input_height(720)
{
// box blurs) until we have what we need.
unsigned mipmap_width = input_width, mipmap_height = input_height;
float adjusted_radius = radius;
- while ((mipmap_width > 1 || mipmap_height > 1) && adjusted_radius * 1.5f > NUM_TAPS / 2) {
+ while ((mipmap_width > 1 || mipmap_height > 1) && adjusted_radius * 1.5f > num_taps / 2) {
// Find the next mipmap size (round down, minimum 1 pixel).
mipmap_width = max(mipmap_width / 2, 1u);
mipmap_height = max(mipmap_height / 2, 1u);
ok |= hpass->set_int("height", mipmap_height);
ok |= hpass->set_int("virtual_width", mipmap_width);
ok |= hpass->set_int("virtual_height", mipmap_height);
+ ok |= hpass->set_int("num_taps", num_taps);
ok |= vpass->set_float("radius", adjusted_radius);
ok |= vpass->set_int("width", mipmap_width);
ok |= vpass->set_int("height", mipmap_height);
ok |= vpass->set_int("virtual_width", input_width);
ok |= vpass->set_int("virtual_height", input_height);
+ ok |= vpass->set_int("num_taps", num_taps);
assert(ok);
}
return false;
}
+bool BlurEffect::set_int(const string &key, int value) {
+ if (key == "num_taps") {
+ if (value < 2 || value % 2 != 0) {
+ return false;
+ }
+ num_taps = value;
+ update_radius();
+ return true;
+ }
+ return false;
+}
+
SingleBlurPassEffect::SingleBlurPassEffect(BlurEffect *parent)
: parent(parent),
+ num_taps(16),
radius(3.0f),
direction(HORIZONTAL),
width(1280),
register_int("height", &height);
register_int("virtual_width", &virtual_width);
register_int("virtual_height", &virtual_height);
+ register_int("num_taps", &num_taps);
}
string SingleBlurPassEffect::output_fragment_shader()
{
char buf[256];
- sprintf(buf, "#define DIRECTION_VERTICAL %d\n", (direction == VERTICAL));
+ sprintf(buf, "#define DIRECTION_VERTICAL %d\n#define NUM_TAPS %d\n",
+ (direction == VERTICAL), num_taps);
return buf + read_file("blur_effect.frag");
}
// Compute the weights; they will be symmetrical, so we only compute
// the right side.
- float weight[NUM_TAPS + 1];
+ float* weight = new float[num_taps + 1];
if (radius < 1e-3) {
weight[0] = 1.0f;
- for (unsigned i = 1; i < NUM_TAPS + 1; ++i) {
+ for (int i = 1; i < num_taps + 1; ++i) {
weight[i] = 0.0f;
}
} else {
float sum = 0.0f;
- for (unsigned i = 0; i < NUM_TAPS + 1; ++i) {
+ for (int i = 0; i < num_taps + 1; ++i) {
// 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
// long-tail. This is a simple logistic distribution, which has
sum += 2.0f * weight[i];
}
}
- for (unsigned i = 0; i < NUM_TAPS + 1; ++i) {
+ for (int i = 0; i < num_taps + 1; ++i) {
weight[i] /= sum;
}
}
//
// We pack the parameters into a float4: The relative sample coordinates
// in (x,y), and the weight in z. w is unused.
- float samples[2 * (NUM_TAPS / 2 + 1)];
+ float* samples = new float[2 * (num_taps / 2 + 1)];
// Center sample.
samples[2 * 0 + 0] = 0.0f;
samples[2 * 0 + 1] = weight[0];
// All other samples.
- for (unsigned i = 1; i < NUM_TAPS / 2 + 1; ++i) {
+ for (int i = 1; i < num_taps / 2 + 1; ++i) {
unsigned base_pos = i * 2 - 1;
float w1 = weight[base_pos];
float w2 = weight[base_pos + 1];
-
- float offset, total_weight;
- combine_two_samples(w1, w2, &offset, &total_weight, NULL);
-
+ int size;
if (direction == HORIZONTAL) {
- samples[2 * i + 0] = (base_pos + offset) / (float)width;
+ size = width;
} else if (direction == VERTICAL) {
- samples[2 * i + 0] = (base_pos + offset) / (float)height;
+ size = height;
} else {
assert(false);
}
+ float pos1 = base_pos / (float)size;
+ float pos2 = (base_pos + 1) / (float)size;
+ float pos, total_weight;
+ combine_two_samples(w1, w2, pos1, pos2, size, &pos, &total_weight, NULL);
+
+ samples[2 * i + 0] = pos;
samples[2 * i + 1] = total_weight;
}
- set_uniform_vec2_array(glsl_program_num, prefix, "samples", samples, NUM_TAPS / 2 + 1);
+ set_uniform_vec2_array(glsl_program_num, prefix, "samples", samples, num_taps / 2 + 1);
+
+ delete[] weight;
+ delete[] samples;
}
void SingleBlurPassEffect::clear_gl_state()