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我目前正在尝试学习 3D，并尝试在使用 3d 数组和所有有趣的东西时获得一些乐趣。我似乎无法理解为什么我的代码没有渲染正确的立方体...我运行一个 3D 数组并分配随机状态（1 个绘制，2 个不绘制）我无法弄清楚为什么当我运行它的状态时似乎只画了所有的立方体或没有。

任何帮助表示赞赏，请原谅糟糕的代码。

编辑：（我添加了一个 cout 文件并修复了一些代码）

#include <iostream>
#include <cstring>
#include <cstdlib>
#include <windows.h>
#include <time.h>


#include <SDL.h>
#include <GL/gl.h>
#include <GL/glu.h>
using namespace std;


float SCALE = 2;
int i;
int chunk[16][16][16];
int chunkSize = 16;
time_t seconds;
int seed = 0;
int colors;

void buildChunk();
void renderChunk();

void drawCube(float size,int x,int y,int z)
{


    glBegin(GL_QUADS);

    // front face
    glColor3f(0,200,255);
    glVertex3f(size/2*x,size/2+y,size/2+z);
    glVertex3f(-size/2*x,size/2+y,size/2+z);
    glVertex3f(-size/2*x,-size/2+y,size/2+z);
    glVertex3f(size/2*x,-size/2+y,size/2+z);
    // left face
    glColor3f(0.0,1.0,0.0);
    glVertex3f(-size/2*x,size/2+y,size/2+z);
    glVertex3f(-size/2*x,-size/2+y,size/2+z);
    glVertex3f(-size/2*x,-size/2+y,-size/2+z);
    glVertex3f(-size/2*x,size/2+y,-size/2+z);
    // back face
    glColor3f(0.0,0.0,1.0);
    glVertex3f(size/2*x,size/2+y,-size/2+z);
    glVertex3f(-size/2*x,size/2+y,-size/2+z);
    glVertex3f(-size/2*x,-size/2+y,-size/2+z);
    glVertex3f(size/2*x,-size/2+y,-size/2+z);
    // right face
    glColor3f(1.0,1.0,0.0);
    glVertex3f(size/2*x,size/2+y,size/2+z);
    glVertex3f(size/2*x,-size/2+y,size/2+z);
    glVertex3f(size/2*x,-size/2+y,-size/2+z);
    glVertex3f(size/2*x,size/2+y,-size/2+z);
    // top face
    glColor3f(1.0,0.0,1.0);
    glVertex3f(size/2*x,size/2+y,size/2+z);
    glVertex3f(-size/2*x,size/2+y,size/2+z);
    glVertex3f(-size/2*x,size/2+y,-size/2+z);
    glVertex3f(size/2*x,size/2+y,-size/2+z);
    // bottom face
    glColor3f(0.0,1.0,1.0);
    glVertex3f(size/2*x,-size/2+y,size/2+z);
    glVertex3f(-size/2*x,-size/2+y,size/2+z);
    glVertex3f(-size/2*x,-size/2+y,-size/2+z);
    glVertex3f(size/2*x,-size/2+y,-size/2+z);
    glEnd();
}

float angle = 0.0;
const int triangle = 1;

void init()
{

    glClearColor(0.0,0.0,0.0,1.0);  //background color and alpha
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    gluPerspective(45,640.0/480.0,1.0,500.0);
    glMatrixMode(GL_MODELVIEW);
    glEnable(GL_DEPTH_TEST);
    buildChunk();
}

void render()
{

    renderChunk();
    glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
    glLoadIdentity();
    glTranslatef(0.0,0.0,-30.0);
    glRotatef(angle,1.0,1.0,0.0);   // angle, x-axis, y-axis, z-axis
}

int main(int argc, char** argv)
{
    SDL_Init(SDL_INIT_EVERYTHING);
    SDL_Surface *screen;
    screen = SDL_SetVideoMode(640, 480, 8, SDL_SWSURFACE|SDL_OPENGL);
//     screen = SDL_SetVideoMode(640, 480, 8, SDL_SWSURFACE|SDL_FULLSCREEN);
    bool running = true;
    const int FPS = 30;
    Uint32 start;
    SDL_Event event;
    init();
    while(running)
    {
        start = SDL_GetTicks();
        while(SDL_PollEvent(&event))
        {
            switch(event.type)
            {
            case SDL_QUIT:
                running = false;
                break;
            }
        }

        render();
        SDL_GL_SwapBuffers();
        angle += 0.5;
        if(angle > 360)
            angle -= 360;
        if(1000/FPS > SDL_GetTicks()-start)
            SDL_Delay(1000/FPS-(SDL_GetTicks()-start));
    }
    SDL_Quit();
    return 0;
}

void buildChunk()
{
    seconds = time (NULL);
    seed = seconds;
    srand(seed);
    /* Seed the random number generator with the specified seed */
    int x;
    int y;
    int z;



    for(x=0; x < chunkSize; x++)
    {
        for(y=0; y < chunkSize; y++)
        {
            for(z=0; z < chunkSize; z++)
            {




                /* 50% chance for a cell to be alive */
                if(rand() % 100 < 50)
                {
                    chunk[x][y][z] = 1;
                }
                else
                {
                    chunk[x][y][z] = 0;
                }
                cout<< "chunk[" << x << "][" << y << "][" << z << "]  state: " << chunk[x][y][z]<<endl;

            }
        }
    }
}

void renderChunk()
{
    int x;
    int y;
    int z;

    for(x=0; x < chunkSize; x++)
    {
        for(y=0; y < chunkSize; y++)
        {
            for(z=0; z < chunkSize; z++)
            {

                if(chunk[x][y][z] == 1)
                {
                    drawCube(1,x,y,z);
                }


            }
        }
    }
}
4

1 回答 1

2

请注意，在所有 glVertex3f 调用的第一列中都有一个“*”符号。这应该是一个“+”，以将顶点偏移 x 而不是缩放它。您可能还需要考虑按大小缩放每个立方体的大小。你最终会得到类似的东西：

    浮动 halfSize = 大小 / 2;
    浮动 xSize = x * 大小；
    浮动 ySize = y * 大小；
    浮动 zSize = z * 大小；

    //正面
    glColor3f(0,200,255);
    glVertex3f(xsize + halfSize, ysize + halfSize, zsize + halfSize);
    glVertex3f(xsize - halfSize, ysize + halfSize, zsize + halfSize);
    glVertex3f(xsize - halfSize, ysize - halfSize, zsize + halfSize);
    glVertex3f(xsize + halfSize, ysize - halfSize, zsize + halfSize);
于 2013-07-19T04:49:02.210 回答