过去几周我一直在学习 OpenGL，在阅读了 Swiftless tuts 和 Nehe 的部分 tuts 以及其他有关法线、场景图、bla bla 的文章之后，我决定创建某种“框架”，以让我更容易地插入新学的代码。所以我决定创建一个场景图/渲染器组合，不是那么漂亮，不是那么快（prolly），但是可以选择添加一个新的派生节点类来渲染一个我可能刚刚读过的新特性。因此，我在 interwebz 上查看了有关如何实现一个并解决此基类的各种示例：
#pragma once
#ifndef NODE_H
#define NODE_H
#include <stdlib.h>
#include <stdio.h>
#include <iostream>
#include <GL/glew.h>
#include <GL/freeglut.h>
#include <GL/glext.h>
#include <math.h>
#include <windows.h>
#include <list>
using namespace std;
class Node
{
public:
Node(void);
~Node(void);
//Node* parent;
void addChild(Node* node);
void removeChilds(Node* node);
virtual void traverse();
void kill();
protected:
std::list<Node*> childs;
};
#endif
....我从中做了这门课：
#pragma once
#ifndef NODESPHERE_H
#define NODESPHERE_H
#include <stdlib.h>
#include <stdio.h>
#include <iostream>
#include <GL/glew.h>
#include <GL/freeglut.h>
#include <GL/glext.h>
#include <math.h>
#include <windows.h>
#include "Various.h"
#include "Node.h"
class NodeSphere : public Node
{
public:
NodeSphere(double R, double H, double K, double Z, const int space);
~NodeSphere(){delete this;}
void traverse();
private:
float out[3];
int Radius;
int vhVertexCount;
Vert *vhVertices;
Normal *vhNormals,*vhVNormals;
TexCoord *vhTexCoords;
unsigned int vhVBOVertices;
unsigned int vhVBOTexCoords;
unsigned int vhVBONormals;
bool Init(void);
bool Normals(const int nIndex);
bool ReduceToUnit(void);
};
#endif
现在，我使用 freeglut 来处理窗口创建和循环：
#include <windows.h>
#include <stdlib.h>
#include <stdio.h>
#include <iostream>
#include <GL/glew.h>
#include <GL/freeglut.h>
#include <GL/glext.h>
#include <math.h>
#include "Scenegraph.h"
#include "View.h"
#include "Control.h"
#define WIDTH 800
#define HEIGHT 600
Scenegraph *bob;
View *myView;
Control *controler;
.................
.................
void main(int argc, char **argv)
{
glewInit();
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH);
glutInitWindowSize(WIDTH,HEIGHT);
glutInitWindowPosition(0,0);
glutCreateWindow("Mediensoftware - Finale Übung");
bob = new Scenegraph();
myView = new View(WIDTH, HEIGHT, bob);
controler = new Control(myView);
glutDisplayFunc(display);
glutIdleFunc(idle);
glutReshapeFunc(resize);
glutKeyboardFunc(keyboard);
glutSpecialFunc(keyboard_s);
glutMainLoop();
}
场景图形“bob”处理节点的创建，如下所示：
Scenegraph::Scenegraph()
{
this->root = new Node();
this->sun = new NodeSphere(3,0,0,0,10);
this->sun_transform = new NodeTransform();
this->sun_tex = new NodeTexture("sunmap.bmp");
this->sun_mat = new NodeMaterial(1.0,0,1.0,0.7,0,1.0,1.0,1.0,0.0,0.0,0.0,0.0,0.0,0.0);
this->planet_earth = new NodeSphere(1,0,0,0,10);
this->planet_earth_transform = new NodeTransform(6,0,0);
this->planet_earth_tex = new NodeTexture("earthmap.bmp");
this->planet_earth_mat = new NodeMaterial(1.0,0,1.0,0.7,0,1.0,1.0,1.0,0.0,0.0,0.0,0.0,0.0,0.0);
this->moon = new NodeSphere(0.3,0,0,0,10);
this->moon_tex = new NodeTexture("moonmap.bmp");
this->moon_transform = new NodeTransform(1.5,0,0);
this->moon_mat = new NodeMaterial(1.0,0,1.0,0.7,0,1.0,1.0,1.0,0.0,0.0,0.0,0.0,0.0,0.0);
this->planet_venus = new NodeSphere(0.8,0,0,0,10);
this->planet_venus_transform = new NodeTransform(3,0,0);
this->planet_venus_tex = new NodeTexture("venusmap.bmp");
this->planet_venus_mat = new NodeMaterial(1.0,0,1.0,0.7,0,1.0,1.0,1.0,0.0,0.0,0.0,0.0,0.0,0.0);
this->planet_mars = new NodeSphere(0.6,0,0,0,10);
................................................................................................
this->root->addChild(this->sun_transform);
this->sun_transform->addChild(this->sun_mat);
this->sun_mat->addChild(this->sun_tex);
this->sun_tex->addChild(this->sun);
this->sun->addChild(this->planet_venus_transform);
this->planet_venus_transform->addChild(this->planet_venus_mat);
this->planet_venus_mat->addChild(this->planet_venus_tex);
...................................................................................................
}
编译器看不到任何错误并执行代码，但它在此处收到访问冲突：
bool NodeSphere::Init(void){
glGenBuffersARB(1, &vhVBOVertices); // DERP here
glBindBufferARB(GL_ARRAY_BUFFER_ARB, this->vhVBOVertices);
glBufferDataARB(GL_ARRAY_BUFFER_ARB, this->vhVertexCount * 3 * sizeof(float), this->vhVertices, GL_STATIC_DRAW_ARB);
glGenBuffersARB(1, &vhVBONormals);
glBindBufferARB(GL_ARRAY_BUFFER_ARB, this->vhVBONormals);
glBufferDataARB(GL_ARRAY_BUFFER_ARB, this->vhVertexCount * 3 * sizeof(float), this->vhVNormals, GL_STATIC_DRAW_ARB);
glGenBuffersARB(1, &vhVBOTexCoords);
glBindBufferARB(GL_ARRAY_BUFFER_ARB, this->vhVBOTexCoords);
glBufferDataARB(GL_ARRAY_BUFFER_ARB, this->vhVertexCount * 2 * sizeof(float), this->vhTexCoords, GL_STATIC_DRAW_ARB);
delete [] vhVertices;
vhVertices = NULL;
delete [] vhTexCoords;
vhTexCoords = NULL;
delete [] vhNormals;
vhNormals = NULL;
delete [] vhVNormals;
vhVNormals = NULL;
return true;
}
扩展在 View::initExtensions() 中调用，场景图的初始化是在窗口创建之后完成的，所以....我很确定它与指针有关...
在以前的程序中，我使用完全相同的代码来创建 VBO，并且它有效。唯一的区别是这里使用的代码在 Node* 中使用，而之前的代码仅在 Node 中使用（没有指针）。但无论如何，我要检查 glew 是否启动良好。至于我使用的是什么显卡，在笔记本电脑上我有一个糟糕的英特尔集成卡，它应该支持 OpenGL 1.5，但甚至没有 GLSL，在 PC 上，一个 6850。问题是我工作了很多在笔记本电脑上，因为教师和其他东西也是如此。
但无论如何，创建 VBO 作品的代码，我的意思是，它适用于以下方面：
#include <stdlib.h>
#include <windows.h>
#include <iostream>
#include <stdio.h>
#include <GL/glew.h>
#include <GL/gl.h> // Header File For The OpenGL32 Library
#include <GL/glu.h> // Header File For The GLu32 Library
#include <GL/glext.h>
#include <math.h>
#define PI 3.14159265f
class Vert{
public:
float x;
float y;
float z;
};
class Normal{
public:
float x;
float y;
float z;
};
class TexCoord{
public:
float u;
float v;
};
class Scenegraph {
private:
float out[3];
int Radius;
GLuint tID[2];
int vhVertexCount;
Vert *vhVertices;
Normal *vhNormals,*vhVNormals;
TexCoord *vhTexCoords;
unsigned int vhVBOVertices;
unsigned int vhVBOTexCoords;
unsigned int vhVBONormals;
bool Init(void);
bool Normals(const int nIndex);
bool ReduceToUnit(void);
public:
bool Create(double R, double H, double K, double Z, const int space);
void Render();
};
它与 NodeSphere 相同，只是它是静态声明的。提前致谢。