+#include <GL/glew.h>
+#include <assert.h>
+#include <math.h>
#include <stdio.h>
+#include <stdlib.h>
#include <string.h>
-#include <assert.h>
+#include <Eigen/Core>
-#include <math.h>
+#include "init.h"
#include "util.h"
-#include "opengl.h"
+
+using namespace std;
+
+namespace movit {
+
+extern string *movit_data_directory;
void hsv2rgb(float h, float s, float v, float *r, float *g, float *b)
{
}
}
-std::string read_file(const std::string &filename)
+string read_file(const string &filename)
{
+ const string full_pathname = *movit_data_directory + "/" + filename;
+
static char buf[131072];
- FILE *fp = fopen(filename.c_str(), "r");
+ FILE *fp = fopen(full_pathname.c_str(), "r");
if (fp == NULL) {
- perror(filename.c_str());
+ perror(full_pathname.c_str());
exit(1);
}
int len = fread(buf, 1, sizeof(buf), fp);
fclose(fp);
- return std::string(buf, len);
+ return string(buf, len);
}
-GLuint compile_shader(const std::string &shader_src, GLenum type)
+GLuint compile_shader(const string &shader_src, GLenum type)
{
GLuint obj = glCreateShader(type);
const GLchar* source[] = { shader_src.data() };
glGetShaderInfoLog(obj, log_length, &log_length, info_log);
info_log[log_length] = 0;
if (strlen(info_log) > 0) {
- printf("shader compile log: %s\n", info_log);
+ fprintf(stderr, "Shader compile log: %s\n", info_log);
}
GLint status;
printf("\n");
}
-std::string output_glsl_mat3(const std::string &name, const Eigen::Matrix3d &m)
+string output_glsl_mat3(const string &name, const Eigen::Matrix3d &m)
{
char buf[1024];
sprintf(buf,
return buf;
}
-void combine_two_samples(float w1, float w2, float *offset, float *total_weight)
+void combine_two_samples(float w1, float w2, float *offset, float *total_weight, float *sum_sq_error)
{
+ assert(movit_initialized);
assert(w1 * w2 >= 0.0f); // Should not have differing signs.
+ float z; // Just a shorter name for offset.
if (fabs(w1 + w2) < 1e-6) {
- *offset = 0.5f;
- *total_weight = 0.0f;
+ z = 0.5f;
} else {
- *offset = w2 / (w1 + w2);
- *total_weight = w1 + w2;
+ z = w2 / (w1 + w2);
}
+
+ // Round to the minimum number of bits we have measured earlier.
+ // The card will do this for us anyway, but if we know what the real z
+ // is, we can pick a better total_weight below.
+ z = lrintf(z / movit_texel_subpixel_precision) * movit_texel_subpixel_precision;
+
+ // Choose total weight w so that we minimize total squared error
+ // for the effective weights:
+ //
+ // e = (w(1-z) - a)² + (wz - b)²
+ //
+ // Differentiating by w and setting equal to zero:
+ //
+ // 2(w(1-z) - a)(1-z) + 2(wz - b)z = 0
+ // w(1-z)² - a(1-z) + wz² - bz = 0
+ // w((1-z)² + z²) = a(1-z) + bz
+ // w = (a(1-z) + bz) / ((1-z)² + z²)
+ //
+ // If z had infinite precision, this would simply reduce to w = w1 + w2.
+ *total_weight = (w1 * (1 - z) + w2 * z) / (z * z + (1 - z) * (1 - z));
+ *offset = z;
+
+ if (sum_sq_error != NULL) {
+ float err1 = *total_weight * (1 - z) - w1;
+ float err2 = *total_weight * z - w2;
+ *sum_sq_error = err1 * err1 + err2 * err2;
+ }
+
assert(*offset >= 0.0f);
assert(*offset <= 1.0f);
}
+
+GLuint fill_vertex_attribute(GLuint glsl_program_num, const string &attribute_name, GLint size, GLenum type, GLsizeiptr data_size, const GLvoid *data)
+{
+ int attrib = glGetAttribLocation(glsl_program_num, attribute_name.c_str());
+ if (attrib == -1) {
+ return -1;
+ }
+
+ GLuint vbo;
+ glGenBuffers(1, &vbo);
+ check_error();
+ glBindBuffer(GL_ARRAY_BUFFER, vbo);
+ check_error();
+ glBufferData(GL_ARRAY_BUFFER, data_size, data, GL_STATIC_DRAW);
+ check_error();
+ glEnableVertexAttribArray(attrib);
+ check_error();
+ glVertexAttribPointer(attrib, size, type, GL_FALSE, 0, BUFFER_OFFSET(0));
+ check_error();
+ glBindBuffer(GL_ARRAY_BUFFER, 0);
+ check_error();
+
+ return vbo;
+}
+
+void cleanup_vertex_attribute(GLuint glsl_program_num, const string &attribute_name, GLuint vbo)
+{
+ int attrib = glGetAttribLocation(glsl_program_num, attribute_name.c_str());
+ if (attrib == -1) {
+ return;
+ }
+
+ glDisableVertexAttribArray(attrib);
+ check_error();
+ glDeleteBuffers(1, &vbo);
+ check_error();
+}
+
+unsigned div_round_up(unsigned a, unsigned b)
+{
+ return (a + b - 1) / b;
+}
+
+// Algorithm from http://graphics.stanford.edu/~seander/bithacks.html#RoundUpPowerOf2.
+unsigned next_power_of_two(unsigned v)
+{
+ v--;
+ v |= v >> 1;
+ v |= v >> 2;
+ v |= v >> 4;
+ v |= v >> 8;
+ v |= v >> 16;
+ v++;
+ return v;
+}
+
+} // namespace movit