#include "blur_effect.h"
#include "effect_chain.h"
#include "effect_util.h"
+#include "init.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)
{
// The first blur pass will forward resolution information to us.
hpass = new SingleBlurPassEffect(this);
CHECK(hpass->set_int("direction", SingleBlurPassEffect::HORIZONTAL));
- vpass = new SingleBlurPassEffect(NULL);
+ vpass = new SingleBlurPassEffect(nullptr);
CHECK(vpass->set_int("direction", SingleBlurPassEffect::VERTICAL));
update_radius();
// 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),
- height(720)
+ width(1280),
+ height(720),
+ uniform_samples(nullptr)
{
register_float("radius", &radius);
register_int("direction", (int *)&direction);
register_int("height", &height);
register_int("virtual_width", &virtual_width);
register_int("virtual_height", &virtual_height);
+ register_int("num_taps", &num_taps);
+}
+
+SingleBlurPassEffect::~SingleBlurPassEffect()
+{
+ delete[] uniform_samples;
}
string SingleBlurPassEffect::output_fragment_shader()
{
- return read_file("blur_effect.frag");
+ char buf[256];
+ sprintf(buf, "#define DIRECTION_VERTICAL %d\n#define NUM_TAPS %d\n",
+ (direction == VERTICAL), num_taps);
+ uniform_samples = new float[2 * (num_taps / 2 + 1)];
+ register_uniform_vec2_array("samples", uniform_samples, num_taps / 2 + 1);
+ return buf + read_file("blur_effect.frag");
}
void SingleBlurPassEffect::set_gl_state(GLuint glsl_program_num, const string &prefix, unsigned *sampler_num)
// 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[4 * (NUM_TAPS / 2 + 1)];
// Center sample.
- samples[4 * 0 + 0] = 0.0f;
- samples[4 * 0 + 1] = 0.0f;
- samples[4 * 0 + 2] = weight[0];
- samples[4 * 0 + 3] = 0.0f;
+ uniform_samples[2 * 0 + 0] = 0.0f;
+ uniform_samples[2 * 0 + 1] = weight[0];
+
+ int size;
+ if (direction == HORIZONTAL) {
+ size = width;
+ } else if (direction == VERTICAL) {
+ size = height;
+ } else {
+ assert(false);
+ }
+ float num_subtexels = size / movit_texel_subpixel_precision;
+ float inv_num_subtexels = movit_texel_subpixel_precision / size;
// 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);
-
- float x = 0.0f, y = 0.0f;
-
- if (direction == HORIZONTAL) {
- x = (base_pos + offset) / (float)width;
- } else if (direction == VERTICAL) {
- y = (base_pos + offset) / (float)height;
- } else {
- assert(false);
- }
+ float pos1 = base_pos / (float)size;
+ float pos, total_weight;
+ combine_two_samples(w1, w2, pos1, 1.0 / (float)size, size, num_subtexels, inv_num_subtexels, &pos, &total_weight, nullptr);
- samples[4 * i + 0] = x;
- samples[4 * i + 1] = y;
- samples[4 * i + 2] = total_weight;
- samples[4 * i + 3] = 0.0f;
+ uniform_samples[2 * i + 0] = pos;
+ uniform_samples[2 * i + 1] = total_weight;
}
- set_uniform_vec4_array(glsl_program_num, prefix, "samples", samples, NUM_TAPS / 2 + 1);
+ delete[] weight;
}
void SingleBlurPassEffect::clear_gl_state()