openGLsupport.cpp

#include "opencv2/core.hpp"
#include "opencv2/imgproc.hpp"
#include "opencv2/highgui.hpp"
#include "opencv2/videoio.hpp"

#include <iostream>
#include <string>
#include <sstream>
#include <GL/glut.h>
using namespace cv;
using namespace std;

Mat frame;
GLfloat angle = 0.0;
GLuint texture;
VideoCapture camera;

int loadTexture(){
	if (frame.data ==NULL) return -1;
	glBindTexture (GL_TEXTURE_2D, texture);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
	glPixelStorei(GL_UNPACK_ALIGNMENT, 1);

	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, frame.cols, frame.rows, 0, GL_BGR, GL_UNSIGNED_BYTE, frame.data);
	return 0;
}

void on_opengl(void *param){
	glLoadIdentity();

	//Load Texture
	glBindTexture(GL_TEXTURE_2D, texture);

	//Rotate plane before draw
	glRotatef(angle, 1.0f, 1.0f, 1.0f);

	//Create the plane and set the texture coordinate
	glBegin(GL_QUADS);

		//First point and coordinate texture
		glTexCoord2d(0.0,0.0);
		glVertex2d(-1.0,-1.0);

		//Second point and coordinate texture
		glTexCoord2d(1.0,0.0);
		glVertex2d(+1.0,-1.0);

		//Third point and coordinate texture
		glTexCoord2d(1.0,1.0);
		glVertex2d(+1.0,+1.0);

		//Fourth point and coordinate texture
		glTexCoord2d(0.0,1.0);
		glVertex2d(-1.0,+1.0);

	glEnd;
}

int main(int argc, const char** argv){
	//Open webcam


    	int deviceID = 2;           
    	int apiID = 0;

	camera.open(deviceID + apiID);

	if (!camera.isOpened())
		{
			cout << "ERROR : Can't open camera" << endl;
			return -1;
		}
	//Create new windows
	namedWindow("OpenGL Camera", WINDOW_OPENGL);

	//Enable texture
	glEnable(GL_TEXTURE_2D);
	glGenTextures(1, &texture);
	setOpenGlDrawCallback("OpenGL Camera", on_opengl);

	while(waitKey(300) !='q'){
		camera >> frame;
		//Create first texture
		loadTexture();
		updateWindow("OpenGL Camera");
		angle = angle+4;
	}

	//Destroy windows
	destroyWindow("OpenGL Camera");
	return 0;
}