如需源码请通过博客首页上方的QQ之一联系。

   熟悉OpenGL的点、线属性函数，在之前的基本直线绘制（Bresenham，DDA算法中的一种）基础上,实现用颜色，宽度函数生成不同颜色，粗细和线型的直线，实现用属性函数绘制不同颜色，大小的点。但是线型实现不做要求，所以要完成实现线的颜色的设置和线宽的设置。void lineWidthByDDA(int x0,int y0,int xEnd,int yEnd,int width,float red,float green,float blue)其中前两个参数为开始的坐标值，紧接着两个参数是结束的坐标值，int width是需设置的线宽的值，后面三个参数是设置线的颜色的RGB三基色的值。 下面的两幅图分别表示了3倍线宽（奇数）和6倍线宽（偶数）的情况：

http://s3/small/5e94b1034b2016c8df1e2&690计算机图形学" TITLE="Opengl实现线段的线宽、颜色属性 计算机图形学" />

【注】代码如下：

#include<windows.h>

#ifdef __APPLE__
#include <GLUT/glut.h>
#else
#include <GL/glut.h>
#endif

#include<stdio.h>
#include<stdlib.h>
#include<math.h>

void init (void)
{
    glClearColor (1.0, 1.0, 1.0, 0.0);  // Set display-window color to white.
    glMatrixMode (GL_PROJECTION);       // Set projection parameters.
    gluOrtho2D (0.0, 200.0, 0.0, 150.0);
}

int round(const float a)
{
 return (int)(a+0.5);
}
//使用DDA算法实现线宽和线的颜色的设置，其中前四个参数为起点和终点坐标，中间的一个参数为线宽，后面的三个参数为线的颜色的设置，分别表示红，绿，蓝
void lineWidthByDDA(int x0,int y0,int xEnd,int yEnd,int width,float red,float green,float blue)
{
    glColor3f(red,green,blue);
 int dx = xEnd - x0;
 int dy = yEnd - y0;
 int steps,k;
 float xIncrement,yIncrement,x = x0,y = y0;
    glEnable(GL_POINT_SMOOTH);
    width -= 1;
    int minWidth,maxWidth;
    if (width%2==0){
        minWidth = -width/2;
        maxWidth = width/2;
    }
    else{
        minWidth = -width/2 - 1;
        maxWidth = width/2;
    }
 if(fabs (dx) > fabs(dy)){
  steps = fabs(dy);
        xIncrement = (float)(dx)/(float)(steps);
        yIncrement = (float)(dy)/(float)(steps);
        for (k=0;k<steps;k++)
        {
            glBegin(GL_POINTS);
            for (int i = minWidth;i<=maxWidth;i++){
                glVertex2i(round(x),round(y+i));
            }
            glEnd();
            x += xIncrement;
            y += yIncrement;
        }
 }
 else{
  steps = fabs(dx);
        xIncrement = (float)(dx)/(float)(steps);
        yIncrement = (float)(dy)/(float)(steps);
        for (k=0;k<steps;k++)
        {
            glBegin(GL_POINTS);
            for (int i = minWidth;i<=maxWidth;i++)
                glVertex2i(round(x+i),round(y));
            glEnd();
            x += xIncrement;
            y += yIncrement;
        }
 }
glFlush();
}

void pointFun()
{
 int x0 = 0,y0 = 0,xEnd = 100,yEnd = 100;
 float red = 1.0,green = 0.5,blue = 0.5;
 glClear (GL_COLOR_BUFFER_BIT);
 lineWidthByDDA(x0,y0+1,xEnd,yEnd,5,red,green,blue);
 glFlush();
}

int main (int argc, char** argv)
{

    glutInit (&argc, argv);                         // Initialize GLUT.
    glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB);   // Set display mode.
    glutInitWindowPosition (50, 100);   // Set top-left display-window position.
    glutInitWindowSize (400, 300);      // Set display-window width and height.
    //glutFullScreen();
    glutCreateWindow ("An Example OpenGL Program By Qiu"); // Create display window.
 init();                           // Execute initialization procedure.
    glutDisplayFunc (pointFun);       // Send graphics to display window.
    glutMainLoop ( );// Send graphics to display window.                  // Display everything and wait.
 return 0;
}