我试图在我的OpenGL项目中使用不同的函数创建各种对象,并通过一个名为display()
的函数来调用它们。但是,当我调用两个函数时,只会显示一个函数,另一个不显示,我不知道为什么。
我尝试了以下方法:
#include <windows.h> // for MS Windows
#include <GL/glut.h> // GLUT, include glu.h and gl.h
#include <math.h>
void box() {
glClearColor(1.0f, 1.0f, 1.0f, 1.0f); // Set background color to black and opaque
glClear(GL_COLOR_BUFFER_BIT); // Clear the color buffer (background)
// Draw a Red 1x1 Square centered at origin
glBegin(GL_POLYGON); // Each set of 4 vertices form a quad
glColor3f(1.0f, 0.0f, 0.0f); // Red
glVertex2f(-0.9f, -0.7f);
glVertex2f(-0.9f, 0.7f);
glVertex2f(0.9f, 0.7f);
glVertex2f(0.9f, -0.7f); // x, y
glEnd();
glFlush(); // Render now
}
void triangle()
{
glClearColor(1.0f, 1.0f, 1.0f, 1.0f); // Set background color to black and opaque
glClear(GL_COLOR_BUFFER_BIT);
glBegin(GL_POLYGON); // Each set of 4 vertices form a quad
glColor3f(0.0f, 1.0f, 0.0f); // green
glVertex2f(-0.9f, -0.7f);
glVertex2f(-0.4f, 0.7f);
glVertex2f(0.1f, -0.7f); // x, y
glEnd();
glFlush(); // Render now
}
void display()
{
box();
triangle();
}
/* Main function: GLUT runs as a console application starting at main() */
int main(int argc, char** argv) {
glutInit(&argc, argv);
glutInitWindowSize(1000, 600);// Set the window's initial width & height
glutCreateWindow("OpenGL Setup Test");
//gluOrtho2D(-0.1,0.7,-0.1,0.3); // Create a window with the given title
//glutInitWindowSize(500, 500);// Set the window's initial width & height
glutDisplayFunc(display);// Register display callback handler for window re-paint
glutMainLoop(); // Enter the event-processing loop
return 0;
}
有什么建议吗?
glClear(GL_COLOR_BUFFER_BIT)
清除所有颜色 - apple apple