opengl_opencv_example/main.cpp

112 lines
3.5 KiB
C++

#include <opencv2/core.hpp>
#include <opencv2/core/opengl.hpp>
#include <opencv2/imgcodecs.hpp>
#include <opencv2/imgproc/imgproc.hpp>
#include <opencv2/highgui.hpp>
#include <iostream>
#ifdef __APPLE__
#include <OpenGL/gl.h>
#include <OpenGL/gl3.h>
#include <GLUT/glut.h>
#else
#include <GL/glew.h>
#include <GL/glut.h>
#endif
using namespace cv;
using namespace std;
using namespace std::chrono;
using time_stamp = time_point<system_clock, microseconds>;
Mat image;
GLuint imageTexture;
GLint screenWidth = 0;
GLint screenHeight = 0;
time_stamp ts;
void loadTexture (GLuint& imageTexture1)
{
string image_path = samples::findFile("chart.png");
Mat image = imread(image_path, IMREAD_COLOR);
if (image.empty()) {
cout << "image empty" << endl;
} else {
cout << "loaded " << image_path << endl;
flip(image, image, 0);
#if (CV_VERSION_MAJOR >= 4)
cvtColor(image, image, cv::COLOR_BGR2RGB);
#else
cvtColor(image, image, CV_BGR2RGB);
#endif
//glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
glGenTextures(1, &imageTexture1);
glBindTexture(GL_TEXTURE_2D, imageTexture1);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
// Set texture clamping method
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
glTexImage2D(GL_TEXTURE_2D, // Type of texture
0, // Pyramid level (for mip-mapping) - 0 is the top level
GL_RGB, // Internal colour format to convert to
image.cols, // Image width i.e. 640 for Kinect in standard mode
image.rows, // Image height i.e. 480 for Kinect in standard mode
0, // Border width in pixels (can either be 1 or 0)
GL_RGB, // Input image format (i.e. GL_RGB, GL_RGBA, GL_BGR etc.)
GL_UNSIGNED_BYTE, // Image data type
image.ptr()); // The actual image data itself
}
}
void getScreenDimensions ()
{
if (screenWidth == 0 && screenHeight == 0) {
GLint dims[4] = {0};
glGetIntegerv(GL_VIEWPORT, dims);
screenWidth = dims[2];
screenHeight = dims[3];
cout << screenWidth << "," << screenHeight << endl;
loadTexture(imageTexture);
}
}
void display(void)
{
getScreenDimensions();
ts = time_point_cast<microseconds>(system_clock::now());
glClear(GL_COLOR_BUFFER_BIT);
glEnable(GL_TEXTURE_2D);
//glViewport(0, 0, screenWidth, screenHeight);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glBindTexture(GL_TEXTURE_2D, imageTexture);
glBegin(GL_QUADS); // front face
glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, -1.0f, 0.0f); //bottom right
glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f, 1.0f, 0.0f); //top right
glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, 1.0f, 0.0f); //top left
glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, -1.0f, 0.0f); //bottom left
glEnd();
glDisable(GL_TEXTURE_2D);
glutSwapBuffers();
//glFlush();
}
int main(int argc, char** argv)
{
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_SINGLE);
glutCreateWindow("opengl_opencv_example");
glutFullScreen();
glutDisplayFunc(display);
glutMainLoop();
return 0;
}