从Image到OpenGL中用户定义的点集（点 Cloud ）的纹理映射

我在世界上有一套三维点 . 使用OpenCV我已经校准了相机的外部参数 .

所以现在我能够将3-D点映射到2-D图像中的相应像素 .

即[X Y Z]我在图像中有相应的[u v] .

在OpenGL中，我已经对世界三维点进行了规范化并定义了一个表面，我想要完成纹理映射 .

The 3-D surface obtained from the code looks like in the figure below.

3-D SURFACE in OPENGL

It is a bowl shaped surface .

现在我想将图像中的纹理映射到OpenGL中的三维点 .

我有的信息：

1. 3-D co-ordinates of a parabolic surface in openGL obtained from world points.

2. Corresponding 2-D Image coordinates and R-G-B colour info of pixels.

我该怎么做呢

Here is my code snippet for getting the 3-D points lying on the model surface shown in the link, using real world coordinates

Also it stores the corresponding (u v) pixel coordinate's RGB colour info in image for rendering ：

for (int z_3D = 0; z_3D < 30; z_3D+=1)
{
    for (int x_3D = 0; x_3D < 102; x_3D+=1)
    {
        for (int y_3D = 0; y_3D < 135.5; y_3D+=1)
        {

            //3-D point in real world(in cms)
            x = x_3D;
            y = y_3D;
            z = z_3D;
            object_point[0].x = x;
            object_point[1].y = y;
            object_point[2].z = z;


            //Project 3-D point to 2-D image and get the corresponding (u,v)
            //rvec and tvec Obtained using SolvPnP in openCV
            projectPoints(object_point, rvec_front, tvec_front, cameraMatrix_Front, distCoeffs_Front, check_front_image_pts);


            //Store colour information in the corresponding 2-D point
            //Points not lying on the surface is black
            rgb.r = 0;
            rgb.g = 0;
            rgb.b = 0;



            //Convert real world coordinates into openGl coordinates(-1 to +1)
            x = (x - CHART_WIDTH / 2) / (CHART_WIDTH / 2);
            y = -(y - CHART_LENGTH / 2) / (CHART_LENGTH / 2);
            z = z / CHART_HEIGHT;


            //Parabolic surface model
            float x_4 = x*x*x*x;
            float y_4 = y*y*y*y;


            if (x_4 + y_4 <  r_4)
            {           
                //Store 3-D point
                vertex_obj.vertex_x.push_back(x);
                vertex_obj.vertex_y.push_back(y);
                vertex_obj.vertex_z.push_back((x_4 + y_4) / (a_4));

                /**/
                //Store colour information in the corresponding 2-D point
                rgb.r = front.at<Vec3b>(check_front_image_pts[0].y, check_front_image_pts[0].x)[2];
                rgb.g = front.at<Vec3b>(check_front_image_pts[0].y, check_front_image_pts[0].x)[1];
                rgb.b = front.at<Vec3b>(check_front_image_pts[0].y, check_front_image_pts[0].x)[0];

                //printf("%f %f %f\n", rgb.r, rgb.g, rgb.b);


                vertex_obj.vertex_colour.push_back(rgb);

            }
            else if (sqrt((x_4 + y_4 - r_4)*(x_4 + y_4 - r_4)) < 0.0001)
            {

                //Store 3-D point
                vertex_obj.vertex_x.push_back(x);
                vertex_obj.vertex_y.push_back(y);
                //vertex_obj.vertex_z.push_back(1.0);
                vertex_obj.vertex_z.push_back((x_4 + y_4) / (a_4)+0.0001);

                /*
                //Store colour information in the corresponding 2-D point
                rgb.r = front.at<Vec3b>(check_front_image_pts[0].y, check_front_image_pts[0].x)[2];
                rgb.g = front.at<Vec3b>(check_front_image_pts[0].y, check_front_image_pts[0].x)[1];
                rgb.b = front.at<Vec3b>(check_front_image_pts[0].y, check_front_image_pts[0].x)[0];*/

                vertex_obj.vertex_colour.push_back(rgb);

            }

        }
    }
}

This is my rendering code snippet

void render()
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);


glLoadIdentity();                 // Reset the model-view matrix

glRotated(ph, 1, 0, 0);
glRotated(th, 0, 1, 0);

glBegin(GL_POINTS);

for (int i = 0; i < vertex_obj.vertex_x.size(); i++)
{
    //Give the colour info from the pixel in the image
    glColor3f(vertex_obj.vertex_colour[i].r/255.0, vertex_obj.vertex_colour[i].g/255.0, vertex_obj.vertex_colour[i].b/255.0);

    //Give the vertex of points lying on the surface defined
    glVertex3f(vertex_obj.vertex_x[i], vertex_obj.vertex_y[i], vertex_obj.vertex_z[i]);
}


//glColor3f(0, 0, 1);
//glVertex2f(1.0, -1.0);

glEnd();


glutSwapBuffers();

}

QUESTIIONS

• 如何使用图像填充曲面 .

I am aware that only a part of the surface is going to be filled based on the 3-D and the corresponding 2-D image coordinates.

• 另外如果我给顶点赋予颜色，我该如何在空隙中插入颜色 . OpenGL插入已知形状，如三角形和四边形 .

但这几乎是一个随机点 Cloud ，我想在最近的像素之间进行插值 .

我该怎么做呢 .