关于c ++：OpenGL：Skybox放大太多了

OpenGL: Skybox magnified too much

我正在尝试在游戏中实现Skybox。我正在使用的图像是：

enter image description here

不幸的是，它被极大地放大了，只显示了纹理的几个像素。看起来像这样：

enter image description here

这是我创建天空盒的代码：

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SkyBox::SkyBox()

{
programID = LoadShaders("Resources/Shaders/skybox.vert","Resources/Shaders/skybox.frag");

pID = glGetUniformLocation(programID,"P");
vID = glGetUniformLocation(programID,"V");

float points[] =
{
-1.0f, 1.0f, -1.0f,
-1.0f, -1.0f, -1.0f,
1.0f, -1.0f, -1.0f,
1.0f, -1.0f, -1.0f,
1.0f, 1.0f, -1.0f,
-1.0f, 1.0f, -1.0f,

-1.0f, -1.0f, 1.0f,
-1.0f, -1.0f, -1.0f,
-1.0f, 1.0f, -1.0f,
-1.0f, 1.0f, -1.0f,
-1.0f, 1.0f, 1.0f,
-1.0f, -1.0f, 1.0f,

1.0f, -1.0f, -1.0f,
1.0f, -1.0f, 1.0f,
1.0f, 1.0f, 1.0f,
1.0f, 1.0f, 1.0f,
1.0f, 1.0f, -1.0f,
1.0f, -1.0f, -1.0f,

-1.0f, -1.0f, 1.0f,
-1.0f, 1.0f, 1.0f,
1.0f, 1.0f, 1.0f,
1.0f, 1.0f, 1.0f,
1.0f, -1.0f, 1.0f,
-1.0f, -1.0f, 1.0f,

-1.0f, 1.0f, -1.0f,
1.0f, 1.0f, -1.0f,
1.0f, 1.0f, 1.0f,
1.0f, 1.0f, 1.0f,
-1.0f, 1.0f, 1.0f,
-1.0f, 1.0f, -1.0f,

-1.0f, -1.0f, -1.0f,
-1.0f, -1.0f, 1.0f,
1.0f, -1.0f, -1.0f,
1.0f, -1.0f, -1.0f,
-1.0f, -1.0f, 1.0f,
1.0f, -1.0f, 1.0f
};
glGenBuffers (1, &vbo);
glBindBuffer (GL_ARRAY_BUFFER, vbo);
glBufferData (GL_ARRAY_BUFFER, sizeof (points), points, GL_STATIC_DRAW);

const char *pth ="/Users/uonibr/Documents/Programming/Space Shooter/Space Shooter/Space Shooter/Resources/space.jpg";

createCubeMap(pth, pth, pth, pth, pth, pth);
}

bool load_cube_map_side (GLuint texture, GLenum side_target, const char* file_name)
{
glBindTexture (GL_TEXTURE_CUBE_MAP, texture);

int x, y;
unsigned char* image_data = SOIL_load_image(file_name, &x, &y, 0, SOIL_LOAD_RGBA);
if (!image_data) {
fprintf (stderr,"ERROR: could not load %s\
", file_name);
return false;
}
// non-power-of-2 dimensions check
if ((x & (x - 1)) != 0 || (y & (y - 1)) != 0) {
fprintf (
stderr,"WARNING: image %s is not power-of-2 dimensions\
", file_name
);
}

// copy image data into 'target' side of cube map
glTexImage2D (
side_target,
0,
GL_RGBA,
x,
y,
0,
GL_RGBA,
GL_UNSIGNED_BYTE,
image_data
);
free (image_data);
return true;
}

void SkyBox::createCubeMap ( const char* front, const char* back, const char* top, const char* bottom, const char* left,const char* right)
{
// generate a cube-map texture to hold all the sides
glActiveTexture (GL_TEXTURE0);
glGenTextures (1, &cubeMap);

// load each image and copy into a side of the cube-map texture
assert(load_cube_map_side (cubeMap, GL_TEXTURE_CUBE_MAP_NEGATIVE_Z, front));
assert(load_cube_map_side (cubeMap, GL_TEXTURE_CUBE_MAP_POSITIVE_Z, back));
assert(load_cube_map_side (cubeMap, GL_TEXTURE_CUBE_MAP_POSITIVE_Y, top));
assert(load_cube_map_side (cubeMap, GL_TEXTURE_CUBE_MAP_NEGATIVE_Y, bottom));
assert(load_cube_map_side (cubeMap, GL_TEXTURE_CUBE_MAP_NEGATIVE_X, left));
assert(load_cube_map_side (cubeMap, GL_TEXTURE_CUBE_MAP_POSITIVE_X, right));

// format cube map texture
glTexParameteri (GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glTexParameteri (GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri (GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_R, GL_CLAMP_TO_EDGE);
glTexParameteri (GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri (GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
}

这是天空盒的渲染代码：

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void SkyBox::render(const Camera &camera) const
{
glDepthMask (GL_FALSE);
glUseProgram (programID);
glActiveTexture (GL_TEXTURE0);
glBindTexture (GL_TEXTURE_CUBE_MAP, cubeMap);
glUniformMatrix4fv(pID, 1, GL_FALSE, &camera.getProjectionMatrix()[0][0]);
glm::mat4 view = camera.getRotationMatrix();
glUniformMatrix4fv(vID, 1, GL_FALSE, &view[0][0]);
glEnableVertexAttribArray (0);
// 1st attribute buffer : vertices
glEnableVertexAttribArray(0);
glBindBuffer(GL_ARRAY_BUFFER, vbo);
glVertexAttribPointer(
0, // attribute. No particular reason for 0, but must match the layout in the shader.
3, // size
GL_FLOAT, // type
GL_FALSE, // normalized?
0, // stride
(void*)0 // array buffer offset
);

glBindBuffer(GL_ARRAY_BUFFER, vbo);
glDrawArrays (GL_TRIANGLES, 0, 36);

glDisableVertexAttribArray(0);
glDepthMask (GL_TRUE);
glCullFace(GL_BACK);

}

片段着色器很简单：

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#version 330 core

in vec3 texcoords;
uniform samplerCube cube_texture;
out vec4 frag_color;

void main () {
frag_color = texture (cube_texture, texcoords);
}

顶点着色器也是如此：

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#version 330 core

in vec3 vp;
uniform mat4 P, V;
out vec3 texcoords;

void main () {
texcoords = vp;
gl_Position = P * V * vec4 (vp, 1.0);

}

编辑：
这是我生成投影矩阵的代码：

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glm::mat4 Camera::getProjectionMatrix() const
{
return glm::perspective(FoV, 4.0f / 3.0f, 0.1f, 100.0f);
}

这是我的FoV：

1	float FoV = 3.14159 * 65. / 180;