gpt4 book ai didi

c++ - 在 OpenGL 中绘制多个形状

转载 作者:塔克拉玛干 更新时间:2023-11-03 01:54:25 26 4
gpt4 key购买 nike

#include <Windows.h>
#include <GL\glut.h>

#pragma comment(lib, "glut32.lib")
#pragma comment(lib, "glu32.lib")
#pragma comment(lib, "opengl32.lib")

#pragma comment(linker, "/subsystem:\"windows\" /entry:\"mainCRTStartup\"")

bool init(void)
{
glClearColor(0.0f, 0.0f, 0.0f, 0.5f);
glMatrixMode(GL_PROJECTION);
// Set grid to be from 0 to 1
gluOrtho2D(0.0, 3.0, 0.0, 3.0);
return true;
}

void drawline(float from_x, float from_y, float to_x, float to_y)
{
// From coordinate position
glVertex2f(from_x, from_y);

// To coordinate position
glVertex2f(to_x, to_y);
}

void render(void)
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glColor3f(1.0, 1.0, 0.0); // Color (RGB): Yellow
glLineWidth(2.0); // Set line width to 2.0
glLoadIdentity();

// Draw line
glBegin(GL_LINES);
drawline(0.25, 0.5, 0.4, 0.5);
drawline(0.4, 0.6, 0.4, 0.5);
drawline(0.4, 0.4, 0.4, 0.5);
drawline(0.6, 0.5, 0.75, 0.5);
glEnd();

// Draw triangle
glBegin(GL_TRIANGLES);
glVertex2f(0.4, 0.5);
glVertex2f(0.6, 0.6);
glVertex2f(0.6, 0.4);
glEnd();

glutSwapBuffers();
}

void reshape(int w, int h)
{
glViewport(0, 0, w, h);
glMatrixMode(GL_MODELVIEW);
}

int main(int argc, char** argv)
{
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE);
glutInitWindowSize(640, 480);
glutCreateWindow("My OpenGL program");

init();

// Draw shape one
glPushMatrix();
glTranslatef(1.5, 1.5, 0.0);
glutDisplayFunc(render);
glPopMatrix();

// Draw shape two
glPushMatrix();
glTranslatef(2.5, 2.5, 0.0);
glutDisplayFunc(render);
glPopMatrix();

glutReshapeFunc(reshape);

glutMainLoop();
return 0;
}

我正在努力画这样的东西:http://i.imgur.com/JJpbJ7M.png

我不需要整个东西,我只想能够在我想要的位置绘制两个形状。但是,这不起作用,任何人都可以指出我正确的方向吗?

最佳答案

你几乎成功了。

render() 而不是 main() 中绘制形状:

#include <GL/glut.h>

void drawline(float from_x, float from_y, float to_x, float to_y)
{
// From coordinate position
glVertex2f(from_x, from_y);

// To coordinate position
glVertex2f(to_x, to_y);
}

void drawShape()
{
glColor3f(1.0, 1.0, 0.0); // Color (RGB): Yellow
glLineWidth(2.0); // Set line width to 2.0

// Draw line
glBegin(GL_LINES);
drawline(0.25, 0.5, 0.4, 0.5);
drawline(0.4, 0.6, 0.4, 0.5);
drawline(0.4, 0.4, 0.4, 0.5);
drawline(0.6, 0.5, 0.75, 0.5);
glEnd();

// Draw triangle
glBegin(GL_TRIANGLES);
glVertex2f(0.4, 0.5);
glVertex2f(0.6, 0.6);
glVertex2f(0.6, 0.4);
glEnd();
}

void render(void)
{
glClearColor(0.0f, 0.0f, 0.0f, 0.5f);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho( 0.0, 4.0, 0.0, 4.0, -1, 1 );

glMatrixMode(GL_MODELVIEW);
glLoadIdentity();

// Draw shape one
glPushMatrix();
glTranslatef(1.5, 1.5, 0.0);
drawShape();
glPopMatrix();

// Draw shape two
glPushMatrix();
glTranslatef(2.5, 2.5, 0.0);
drawShape();
glPopMatrix();

glutSwapBuffers();
}

int main(int argc, char** argv)
{
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE);
glutInitWindowSize(640, 480);
glutCreateWindow("My OpenGL program");
glutDisplayFunc(render);
glutMainLoop();
return 0;
}

我删除了 reshape()init() 因为默认的 glutReshapeFunc() 已经调用了 glViewport() 无论如何,你应该在每一帧重置你的投影和模型 View 矩阵。

关于c++ - 在 OpenGL 中绘制多个形状,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/19386509/

26 4 0
Copyright 2021 - 2024 cfsdn All Rights Reserved 蜀ICP备2022000587号
广告合作:1813099741@qq.com 6ren.com