opengl_utils.cpp File Reference

#include <vector>
#include <string>
#include <stdexcept>
#include <cassert>
#include "opengl_utils.hpp"
#include "opengl_conversions.hpp"
#include "video_frame.h"
#include "video_codec.h"
#include "color.h"
#include "debug.h"
#include "host.h"
#include "utils/profile_timer.hpp"

Include dependency graph for opengl_utils.cpp:

Go to the source code of this file.

Macros
#define	MOD_NAME   "[Opengl utils] "

Functions
bool	check_gl_extension_present (const char *ext)
static void	compileShader (GLuint shaderId)
static std::vector< unsigned >	gen_sphere_indices (int latitude_n, int longtitude_n)
static std::vector< float >	gen_sphere_vertices (int r, int latitude_n, int longtitude_n)

Variables
static const float	PI_F =3.14159265358979f
static unsigned char	pixels []
static const GLfloat	rectangle []

Detailed Description

Author

Martin Piatka piatk.nosp@m.a@ce.nosp@m.snet..nosp@m.cz

Martin Pulec pulec.nosp@m.@ces.nosp@m.net.c.nosp@m.z

Definition in file opengl_utils.cpp.

Macro Definition Documentation

MOD_NAME

#define MOD_NAME   "[Opengl utils] "

Definition at line 52 of file opengl_utils.cpp.

Function Documentation

check_gl_extension_present()

bool check_gl_extension_present

(

const char *

ext

)

Definition at line 91 of file opengl_utils.cpp.

                                                {
        int count = 0;
        glGetIntegerv(GL_NUM_EXTENSIONS, &count);
 
        for(int i = 0; i < count; i++){
                const char *item = (const char *) glGetStringi(GL_EXTENSIONS, i);
                if(strcmp(item, ext) == 0)
                        return true;
        }
 
        return false;
}

References count.

compileShader()

static void compileShader ( GLuint shaderId )

static

Definition at line 73 of file opengl_utils.cpp.

                                          {
        glCompileShader(shaderId);
 
        GLint ret = GL_FALSE;
        int len;
 
        glGetShaderiv(shaderId, GL_COMPILE_STATUS, &ret);
        glGetShaderiv(shaderId, GL_INFO_LOG_LENGTH, &len);
        if (len > 0){
                std::vector<char> errorMsg(len+1);
                glGetShaderInfoLog(shaderId, len, NULL, &errorMsg[0]);
                printf("%s\n", errorMsg.data());
        }
}

References len.

gen_sphere_indices()

static std::vector< unsigned > gen_sphere_indices ( int latitude_n, int longtitude_n )

static

Definition at line 470 of file opengl_utils.cpp.

                                                                               {
        std::vector<unsigned int> indices;
 
        for(int i = 0; i < latitude_n; i++){
                int slice_idx = i * (latitude_n + 1);
                int next_slice_idx = (i + 1) * (latitude_n + 1);
 
                for(int j = 0; j < longtitude_n; j++){
                        //Since the top and bottom slices are circles with radius 0,
                        //we only need one triangle for those
                        if(i != latitude_n - 1){
                                indices.push_back(slice_idx + j + 1);
                                indices.push_back(next_slice_idx + j);
                                indices.push_back(next_slice_idx + j + 1);
                        }
 
                        if(i != 0){
                                indices.push_back(slice_idx + j + 1);
                                indices.push_back(slice_idx + j);
                                indices.push_back(next_slice_idx + j);
                        }
                }
        }
 
        return indices;
}

Referenced by Model::get_sphere().

gen_sphere_vertices()

static std::vector< float > gen_sphere_vertices ( int r, int latitude_n, int longtitude_n )

static

Definition at line 440 of file opengl_utils.cpp.

                                                                                    {
        std::vector<float> verts;
 
        float lat_step = PI_F / latitude_n;
        float long_step = 2 * PI_F / longtitude_n;
 
        for(int i = 0; i < latitude_n + 1; i++){
                float y = std::cos(i * lat_step) * r;
                float y_slice_r = std::sin(i * lat_step) * r;
 
                //The first and last vertex on the y slice circle are in the same place
                for(int j = 0; j < longtitude_n + 1; j++){
                        float x = std::sin(j * long_step) * y_slice_r;
                        float z = std::cos(j * long_step) * y_slice_r;
                        verts.push_back(x);
                        verts.push_back(y);
                        verts.push_back(z);
 
                        float u = 1 - static_cast<float>(j) / longtitude_n;
                        float v = static_cast<float>(i) / latitude_n;
                        verts.push_back(u);
                        verts.push_back(v);
                }
        }
 
        return verts;
}

References PI_F.

Referenced by Model::get_sphere().

Variable Documentation

PI_F

const float PI_F =3.14159265358979f

static

Definition at line 54 of file opengl_utils.cpp.

Referenced by gen_sphere_vertices().

pixels

unsigned char pixels[]

static

Initial value:

= {
        255, 0, 0,   0, 255, 0,   0, 0, 255,   255, 255, 255,
        255, 0, 0,   0, 255, 0,   0, 0, 255,   255, 255, 255,
        255, 0, 0,   0, 255, 0,   0, 0, 255,   255, 255, 255,
        255, 0, 0,   0, 255, 0,   0, 0, 255,   255, 255, 255
}

Definition at line 66 of file opengl_utils.cpp.

                                {
        255, 0, 0,   0, 255, 0,   0, 0, 255,   255, 255, 255,
        255, 0, 0,   0, 255, 0,   0, 0, 255,   255, 255, 255,
        255, 0, 0,   0, 255, 0,   0, 0, 255,   255, 255, 255,
        255, 0, 0,   0, 255, 0,   0, 0, 255,   255, 255, 255
};

rectangle

const GLfloat rectangle[]

static

Initial value:

= {
        1.0f,  1.0f,  1.0f,  1.0f,
        -1.0f,  1.0f,  0.0f,  1.0f,
        -1.0f, -1.0f,  0.0f,  0.0f,
 
        1.0f,  1.0f,  1.0f,  1.0f,
        -1.0f, -1.0f,  0.0f,  0.0f,
        1.0f, -1.0f,  1.0f,  0.0f
}

Definition at line 56 of file opengl_utils.cpp.

                                   {
        1.0f,  1.0f,  1.0f,  1.0f,
        -1.0f,  1.0f,  0.0f,  1.0f,
        -1.0f, -1.0f,  0.0f,  0.0f,
 
        1.0f,  1.0f,  1.0f,  1.0f,
        -1.0f, -1.0f,  0.0f,  0.0f,
        1.0f, -1.0f,  1.0f,  0.0f
};