我正在尝试使用统一缓冲区,但它不能按预期工作。我有两个统一的缓冲区,一个是灯光,另一个是 Material 。问题在于颜色不是应该的颜色,并且每次我移动相机时它们都会改变。当我使用普通 uniform 时,这个问题不存在。这是显示我的意思的图片:When using uniform buffers和when using normal uniforms!
这是我的片段着色器:
#version 400 // Fragment Shader
uniform layout(std140);
in vec3 EyePosition;
in vec3 EyeNormal;
in vec2 TexCoord;
out vec4 FragColor;
uniform sampler2D Texture;
uniform LightBlock
{
vec4 Position;
vec4 Intensity;
} Light;
uniform MaterialBlock
{
vec4 Ambient;
vec4 Diffuse;
} Material;
vec4 PointLight(in int i, in vec3 ECPosition, in vec3 ECNormal)
{
vec3 n = normalize(ECNormal);
vec3 s = normalize(Light.Position.xyz - ECPosition);
return Light.Intensity * (Material.Ambient + Material.Diffuse * max(dot(s, n), 0.0));
}
void main()
{
FragColor = texture(Texture, TexCoord);
FragColor *= PointLight(0, EyePosition, EyeNormal);
}
我不确定我是否做对了所有事情,但是这是我创建统一缓冲区的方法:
glGenBuffers(1, &light_buffer);
glGenBuffers(1, &material_buffer);
glBindBuffer(GL_UNIFORM_BUFFER, light_buffer);
glBufferData(GL_UNIFORM_BUFFER, sizeof(LightBlock), nullptr, GL_DYNAMIC_DRAW);
glBindBuffer(GL_UNIFORM_BUFFER, material_buffer);
glBufferData(GL_UNIFORM_BUFFER, sizeof(MaterialBlock), nullptr, GL_DYNAMIC_DRAW);
GLuint program = Shaders.GetProgram();
light_index = glGetUniformBlockIndex(program, "LightBlock");
material_index = glGetUniformBlockIndex(program, "MaterialBlock");
glUniformBlockBinding(program, light_index, 0);
glUniformBlockBinding(program, material_index, 1);
glBindBufferBase(GL_UNIFORM_BUFFER, 0, light_buffer);
glBindBufferBase(GL_UNIFORM_BUFFER, 1, material_buffer);
编辑:这是我填充缓冲区的方式:
// Global structures
struct LightBlock
{
Vector4 Position; // Vector4 is a vector class I made
Vector4 Intensity;
};
struct MaterialBlock
{
Vector4 Ambient;
Vector4 Diffuse;
};
// This is called for every object rendered
LightBlock Light;
Light.Position = Vector3(0.0f, 5.0f, 5.0f) * Camera.GetCameraMatrix();
Light.Intensity = Vector4(1.0f);
glBindBuffer(GL_UNIFORM_BUFFER, light_buffer);
glBufferSubData(GL_UNIFORM_BUFFER, 0, sizeof(LightBlock), &Light);
MaterialBlock Material;
Material.Diffuse = Vector4(1.0f);
Material.Ambient = Material.Diffuse * Vector4(0.3f);
glBindBuffer(GL_UNIFORM_BUFFER, material_buffer);
glBufferSubData(GL_UNIFORM_BUFFER, 0, sizeof(MaterialBlock), &Material);
最佳答案
我也遇到了同样的问题,但是只有AMD(不是NVIDIA)。有趣的是,该问题仅在更改 View 矩阵时才会发生。
由于根据 View 矩阵的更改,我遇到了一个可重复的问题,因此我能够追溯到根本原因(进行了艰苦的尝试和错误)。在应用程序中更改 View 时,我会根据需要动态分配和释放一些OpenGL资源。在此过程中,对缓冲区0调用了glDeleteBuffers()。如果我使用条件语句以便不为缓冲区0调用glDeleteBuffers,那么问题就消失了。
根据文档,缓冲区0将被glDeleteBuffers静默忽略。我的猜测是AMD驱动程序中存在错误。
关于c++ - OpenGL统一缓冲区?,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/9155044/