OpenGL统一缓冲区？

Question

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,一个是照明,另一个是材料.问题是颜色不是它们应该是的,并且每次移动相机时颜色都会改变.当我使用普通制服时,这个问题不存在.这是照片,以显示我的意思:当使用统一缓冲区和使用正常制服时!

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);
}

我不确定我做的一切都是正确的,但这是我如何创建统一缓冲区:

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);

Answer 1

我也遇到了同样的问题，但仅限于 AMD（不是 NVIDIA）。有趣的是，这个问题只发生在改变视图矩阵时。

由于根据视图矩阵的变化我遇到了一个可重复的问题，因此我能够追踪到根本原因（进行艰苦的试验和错误）。当更改应用程序中的视图时，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免对缓冲区 0 调用 glDeleteBuffers，那么问题就会消失。

根据文档，缓冲区 0 将被glDeleteBuffers默默忽略。我的猜测是 AMD 驱动程序存在错误。