带 GLUT 的黑屏?

我正在尝试基于此代码进行一些体积渲染。

我现在正在做的是我有一些示例 3D 数据(数组 chBuffer 本质上是一个 4*4*4 测试数据数组(，我正在将其转换为 OpenGL 3D 纹理。之后，我尝试使用其他 OpenGL 命令渲染此纹理。但是，当我运行应用程序时，屏幕完全是黑色的，并显示某些内容。我做错了什么具体的事情应该解决这个问题吗？

这是我的代码：

#include <glut.h>
#include <GL/gl.h>
#include <gl/glext.h>
#include <stdio.h>
#include <Windows.h>
GLfloat dOrthoSize = 1.0f;
GLuint mu3DTex;
#define MAP_3DTEXT( TexIndex ) 
glTexCoord3f(0.0f, 0.0f, ((float)TexIndex+1.0f)/2.0f);  
glVertex3f(-dOrthoSize,-dOrthoSize,TexIndex);
glTexCoord3f(1.0f, 0.0f, ((float)TexIndex+1.0f)/2.0f);  
glVertex3f(dOrthoSize,-dOrthoSize,TexIndex);
glTexCoord3f(1.0f, 1.0f, ((float)TexIndex+1.0f)/2.0f);  
glVertex3f(dOrthoSize,dOrthoSize,TexIndex);
glTexCoord3f(0.0f, 1.0f, ((float)TexIndex+1.0f)/2.0f);  
glVertex3f(-dOrthoSize,dOrthoSize,TexIndex);
void main(int argc, char **argv)
{
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);
glutInitWindowSize(500, 500);
glutCreateWindow("Name");

char* chBuffer = new char[64];
for (int i = 0; i < 64; ++i)
chBuffer[i] = ((i + (i / 8)) % 2) * 128 + 127;

char* chRGBABuffer = new char[256];
glGenTextures(1, (GLuint*)&mu3DTex);

glBindTexture(GL_TEXTURE_3D, mu3DTex);
glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_BORDER);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_BORDER);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_R, GL_CLAMP_TO_BORDER);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);

for (int nIndx = 0; nIndx < 64; ++nIndx)
{
chRGBABuffer[nIndx * 4] = chBuffer[nIndx];
chRGBABuffer[nIndx * 4 + 1] = chBuffer[nIndx];
chRGBABuffer[nIndx * 4 + 2] = chBuffer[nIndx];
chRGBABuffer[nIndx * 4 + 3] = chBuffer[nIndx];
}
glTexImage3D(GL_TEXTURE_3D, 0, GL_RGBA, 4, 4, 4, 0,
GL_RGBA, GL_UNSIGNED_BYTE, (GLvoid *)chRGBABuffer);
glBindTexture(GL_TEXTURE_3D, 0);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glEnable(GL_ALPHA_TEST);
glAlphaFunc(GL_GREATER, 0.03f);
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
glMatrixMode(GL_TEXTURE);
glLoadIdentity();

glEnable(GL_TEXTURE_3D);
glBindTexture(GL_TEXTURE_3D, mu3DTex);
for (float fIndx = -1.0f; fIndx <= 1.0f; fIndx += 0.003f)
{
glBegin(GL_QUADS);
MAP_3DTEXT(fIndx);
glEnd();
}
system("pause");

}