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我可以编译并运行该程序，但它在运行时仅创建一个没有任何内容的白色窗口。我已经确定着色器文件在同一个目录中，并且除了带有白色背景的窗口外，它仍然不会产生任何其他内容。GL或GLUT有问题
//
// Perspective view of a color cube using LookAt() and Frustum()
//
// Colors are assigned to each vertex and then the rasterizer interpolates
// those colors across the triangles.
//
#define _CRT_SECURE_NO_WARNINGS
#include "Angel.h"
typedef Angel::vec4 color4;
typedef Angel::vec4 point4;
const int NumVertices = 36; //(6 faces)(2 triangles/face)(3 vertices/triangle)
point4 points[NumVertices];
color4 colors[NumVertices];
// Vertices of a unit cube centered at origin, sides aligned with axes
point4 vertices[8] = {
point4(-0.5, -0.5, 0.5, 1.0),
point4(-0.5, 0.5, 0.5, 1.0),
point4( 0.5, 0.5, 0.5, 1.0),
point4( 0.5, -0.5, 0.5, 1.0),
point4(-0.5, -0.5, -0.5, 1.0),
point4(-0.5, 0.5, -0.5, 1.0),
point4( 0.5, 0.5, -0.5, 1.0),
point4( 0.5, -0.5, -0.5, 1.0)
};
// RGBA olors
color4 vertex_colors[8] = {
color4(0.0, 0.0, 0.0, 1.0), // black
color4(1.0, 0.0, 0.0, 1.0), // red
color4(1.0, 1.0, 0.0, 1.0), // yellow
color4(0.0, 1.0, 0.0, 1.0), // green
color4(0.0, 0.0, 1.0, 1.0), // blue
color4(1.0, 0.0, 1.0, 1.0), // magenta
color4(1.0, 1.0, 1.0, 1.0), // white
color4(0.0, 1.0, 1.0, 1.0) // cyan
};
// Viewing transformation parameters
GLfloat radius = 1.0;
GLfloat theta = 0.0;
GLfloat phi = 0.0;
const GLfloat dr = 5.0 * DegreesToRadians;
GLuint model_view; // model-view matrix uniform shader variable location
// Projection transformation parameters
GLfloat left = -1.0, right = 1.0;
GLfloat bottom = -1.0, top = 1.0;
GLfloat zNear = 0.5, zFar = 3.0;
GLuint projection; // projection matrix uniform shader variable location
//----------------------------------------------------------------------------
// quad generates two triangles for each face and assigns colors
// to the vertices
int Index = 0;
void
quad(int a, int b, int c, int d)
{
colors[Index] = vertex_colors[a]; points[Index] = vertices[a]; Index++;
colors[Index] = vertex_colors[b]; points[Index] = vertices[b]; Index++;
colors[Index] = vertex_colors[c]; points[Index] = vertices[c]; Index++;
colors[Index] = vertex_colors[a]; points[Index] = vertices[a]; Index++;
colors[Index] = vertex_colors[c]; points[Index] = vertices[c]; Index++;
colors[Index] = vertex_colors[d]; points[Index] = vertices[d]; Index++;
}
//----------------------------------------------------------------------------
// generate 12 triangles: 36 vertices and 36 colors
void
colorcube()
{
quad(1, 0, 3, 2);
quad(2, 3, 7, 6);
quad(3, 0, 4, 7);
quad(6, 5, 1, 2);
quad(4, 5, 6, 7);
quad(5, 4, 0, 1);
}
//----------------------------------------------------------------------------
// OpenGL initialization
void
init()
{
colorcube();
// Create a vertex array object
GLuint vao;
glGenVertexArrays(1, &vao);
glBindVertexArray(vao);
// Create and initialize a buffer object
GLuint buffer;
glGenBuffers(1, &buffer);
glBindBuffer(GL_ARRAY_BUFFER, buffer);
glBufferData(GL_ARRAY_BUFFER, sizeof(points) + sizeof(colors),
NULL, GL_STATIC_DRAW);
glBufferSubData(GL_ARRAY_BUFFER, 0, sizeof(points), points);
glBufferSubData(GL_ARRAY_BUFFER, sizeof(points), sizeof(colors), colors);
// Load shaders and use the resulting shader program
GLuint program = InitShader("vshader42.glsl", "fshader42.glsl");
glUseProgram(program);
// set up vertex arrays
GLuint vPosition = glGetAttribLocation(program, "vPosition");
glEnableVertexAttribArray(vPosition);
glVertexAttribPointer(vPosition, 4, GL_FLOAT, GL_FALSE, 0,
BUFFER_OFFSET(0));
GLuint vColor = glGetAttribLocation(program, "vColor");
glEnableVertexAttribArray(vColor);
glVertexAttribPointer(vColor, 4, GL_FLOAT, GL_FALSE, 0,
BUFFER_OFFSET(sizeof(points)));
model_view = glGetUniformLocation(program, "model_view");
projection = glGetUniformLocation(program, "projection");
glEnable(GL_DEPTH_TEST);
glClearColor(1.0, 1.0, 1.0, 1.0);
}
//----------------------------------------------------------------------------
void
display(void)
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
point4 eye(radius*sin(theta)*cos(phi),
radius*sin(theta)*sin(phi),
radius*cos(theta),
1.0);
point4 at(0.0, 0.0, 0.0, 1.0);
vec4 up(0.0, 1.0, 0.0, 0.0);
mat4 mv = LookAt(eye, at, up);
glUniformMatrix4fv(model_view, 1, GL_TRUE, mv);
mat4 p = Frustum(left, right, bottom, top, zNear, zFar);
glUniformMatrix4fv(projection, 1, GL_TRUE, p);
glDrawArrays(GL_TRIANGLES, 0, NumVertices);
glutSwapBuffers();
}
//----------------------------------------------------------------------------
void
keyboard(unsigned char key, int x, int y)
{
switch(key) {
case 033: // Escape Key
case 'q': case 'Q':
exit(EXIT_SUCCESS);
break;
case 'x': left *= 1.1; right *= 1.1; break;
case 'X': left *= 0.9; right *= 0.9; break;
case 'y': bottom *= 1.1; top *= 1.1; break;
case 'Y': bottom *= 0.9; top *= 0.9; break;
case 'z': zNear *= 1.1; zFar *= 1.1; break;
case 'Z': zNear *= 0.9; zFar *= 0.9; break;
case 'r': radius *= 2.0; break;
case 'R': radius *= 0.5; break;
case 'o': theta += dr; break;
case 'O': theta -= dr; break;
case 'p': phi += dr; break;
case 'P': phi -= dr; break;
case ' ': // reset values to their defaults
left = -1.0;
right = 1.0;
bottom = -1.0;
top = 1.0;
zNear = 0.5;
zFar = 3.0;
radius = 1.0;
theta = 0.0;
phi = 0.0;
break;
}
glutPostRedisplay();
}
//----------------------------------------------------------------------------
void
reshape(int width, int height)
{
glViewport(0, 0, width, height);
}
//----------------------------------------------------------------------------
int
main(int argc, char **argv)
{
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_RGBA | GLUT_DOUBLE | GLUT_DEPTH);
glutInitWindowSize(512, 512);
glutInitContextVersion(3, 2);
glutInitContextProfile(GLUT_CORE_PROFILE);
glutCreateWindow("Color Cube");
glewInit();
init();
glutDisplayFunc(display);
glutKeyboardFunc(keyboard);
glutReshapeFunc(reshape);
glutMainLoop();
return 0;
}