在半渲染正交场景的顶部将OpenGL切换到透视模式?

• 渲染全屏背景
• 将视口设置为位置=obj.pos-obj.size/2,大小=obj.size,渲染对象
• 渲染2D gui

或者你想要别的?

编辑:

下面是一些小代码:

glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho(0,w,0,h,near,far);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glTranslatef(pos.x,...);

DrawQuads();

//if you want to keep your previus matrix
glMatrixMode(GL_PROJECTION);
glPushMatrix();
glLoadIdentity();
gluPerspective(90,width/(float)height,0.001,1000);
glMatrixMode(GL_MODELVIEW);
glPushMatrix();
glLoadIdentity();
glTranslatef(pos.x,...);
glRotate(-45.0f,1,0,0);
glTranslate(0,0,distance from object);
glRotate(90.0f,1,0,0);
// or use gluLookAt
// 0,0,1 - if you want have z as up in view
// 0,1,0 - for y
//gluLookAt(pos.x,pos.y,pos.z,cam.x,cam.y,cam.z,0,0,1);

glScale(object.width/model.width,...);
DrawModel();

// Restore old ortho
glPopMatrix();
glMatrixMode(GL_PROJECTION);
glPopMatrix();
glMatrixMode(GL_MODELVIEW);

好吧,“就这么做”

• 将投影矩阵设置为正交
• 为二维对象设置模型视图
• 渲染2D对象
• 将投影矩阵设置为“投影”
• 为三维对象设置模型视图
• 渲染3D对象

• 交换缓冲区。

我同意前面的文章,我认为更一般的情况是像3D对象和2dgui。

glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective( 45.0f, (GLfloat)s_width/(GLfloat)s_height, near, far);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
// render 3D object
glUseProgram(modelProgram);
glSetUniformMat(glGetUniformLocation(model.mvp, "mvp"), mvpMat);
glBindVertexArray(model.vao);
glDrawArrays(GL_TRIANGLES, 0, model.size);
glUseProgram(0);


glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho(0, width, 0, height, -1.0, 1.0);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
// draw GUI
renderGUI();