5

最近我将 ATI 驱动程序（我正在使用 HD7970）更新到最新的驱动程序，并且我的一些 OpenGL 项目的 objetcs 停止工作。更重要的是，他们在 nVidia 最新驱动程序上工作（在 960m 上测试）。我应该知道 ATI 和 nVidia 渲染管道之间有什么区别吗？

附加信息：

  • glGetError() 没有错误，
  • 着色器正确编译和链接，
  • 其他渲染对象工作正常，但 VBO 填充和绘图命令不同。工作一个从 *.obj 文件加载并由 glDrawArrays() 绘制。Broken one 的 VBO 由多边形化器（计算着色器）填充，它从用于存储的 image2D 中获取顶点，并由 glDrawElements() 绘制，
  • 使用我最简单的 gpu 调试器，我检查了顶点和片段着色器是否正在启动。

当我尝试用三角形绘制时，我什么也看不到，但是当我切换到 GL_POINTS 时，我看到绿点（片段着色器的输出是纯绿色通道）正在按应有的方式移动。这可能表明顶点着色器正在启动，因为 MVP 倍增正在发生。这些是具有一个大 VBO 的行星 LOD 对象，因此我使用一个函数来绑定所有缓冲区和其他函数来绘制必要的高度图。VBO 大小为 128MB

初始化：

glGenBuffers(1, &VBO);
glBindBuffer(GL_SHADER_STORAGE_BUFFER, VBO);
glBufferData(GL_SHADER_STORAGE_BUFFER, size * sizeof(vec4), NULL, GL_DYNAMIC_COPY);

glGenBuffers(1, &IndexBuffer);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, IndexBuffer);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, indexSize * sizeof(unsigned int), NULL, GL_DYNAMIC_DRAW);

glGenBuffers(1, &Normals);
glBindBuffer(GL_SHADER_STORAGE_BUFFER, Normals);
glBufferData(GL_SHADER_STORAGE_BUFFER, size * sizeof(vec4), NULL, GL_DYNAMIC_COPY);

通过多边形化器（计算着色器）填充 VBO：

    #version 430 core
layout( std430, binding=1 ) buffer ParamsBuffer
  {
    float size;
        uint index;
        int parentIndex;
        uint textureSize;
        vec4 upVector;
        vec4 Position;
        vec4 quadrant;
  };
  layout( std430, binding=2 ) buffer VertBuffer
  {
    vec4 VBO[ ]; 
  };

  layout( std430, binding=3 ) buffer NormalsBuffer
  {
    vec4 Normals[ ]; 
  };

 layout(std430, binding = 4) buffer IndexBuffer
{
 uint Index[];
};

  layout( std430, binding=10 ) buffer DebugBuffer
    {
      vec4 debug; 
    };
  layout (rgba32f)  uniform image2D HeightMap;
  layout (rgba32f)  uniform image2D NormalMap;
  layout( local_size_x = 1, local_size_y = 1, local_size_z = 1) in;

  void main(void)
  {
    uint  WGidY=(gl_WorkGroupID.y);
    uint  WGidX=(gl_WorkGroupID.x);
    uint mapVBOOffset=index*textureSize*textureSize;
    uint indexOffset=6*index*textureSize*textureSize;
        VBO[WGidY*textureSize+WGidX+mapVBOOffset]=imageLoad(HeightMap, ivec2(WGidX, WGidY));
    Normals[WGidY*textureSize+WGidX+mapVBOOffset]=imageLoad(NormalMap, ivec2(WGidX, WGidY));
   // debug=VBO[0];
    if(WGidX==textureSize-1 || WGidY==textureSize-1)
    return;

    uint localIndex = 6*(WGidY*textureSize+WGidX)+indexOffset;
    Index[localIndex+0]=(WGidY+1)*textureSize+WGidX  +mapVBOOffset;
    Index[localIndex+1]=WGidY*textureSize    +WGidX+1+mapVBOOffset;
    Index[localIndex+2]=WGidY*textureSize    +WGidX  +mapVBOOffset;
    Index[localIndex+3]=WGidY*textureSize    +WGidX+1+mapVBOOffset;
    Index[localIndex+4]=(WGidY+1)*textureSize+WGidX  +mapVBOOffset;
    Index[localIndex+5]=(WGidY+1)*textureSize+WGidX+1+mapVBOOffset;

  }

捆绑：

    glUseProgram(RenderProgram);
glBindBufferBase(GL_SHADER_STORAGE_BUFFER, 4, PerFrameBuffer);
glBindBufferBase(GL_SHADER_STORAGE_BUFFER, 5, ConstantBuffer);

glEnableVertexAttribArray(2);
glBindBuffer(GL_ARRAY_BUFFER, Normals);
glVertexAttribPointer(
    2,                  
    4,                  
    GL_FLOAT,           
    GL_FALSE,           
    0,                  
    (void*)0            
);


glEnableVertexAttribArray(0);
glBindBuffer(GL_ARRAY_BUFFER, VBO);
glVertexAttribPointer(
    0,                  
    4,                  
    GL_FLOAT,           
    GL_FALSE,           
    0,                 
    (void*)0            
);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, IndexBuffer);

绘画：

float discardFactor = 0;
GLint drawMode;
if(renderMode==0)
 drawMode = GL_TRIANGLES;
if (renderMode == 1)
{
    drawMode = GL_PATCHES;
    GLint vert= 3;
    glPatchParameteri(GL_PATCH_VERTICES, 3);
}
if (tile->quadrant_x == nullptr)
{
        HeightMap hp = tile->quadrantX;
        if (CornersInFrustum(hp.Corners))
        {
            int mapOffset = tile->quadrantX.index * 6 * heightMapSize*heightMapSize * sizeof(unsigned int);
            glDrawElements(drawMode, 6 * heightMapSize*heightMapSize, GL_UNSIGNED_INT, (void*)mapOffset);
        }

}

if (tile->quadrant_y == nullptr)
{
    HeightMap hp = tile->quadrantY;
    if ( CornersInFrustum(hp.Corners))
    {
        int mapOffset = tile->quadrantY.index * 6 * heightMapSize*heightMapSize * sizeof(unsigned int);
        glDrawElements(drawMode, 6 * heightMapSize*heightMapSize, GL_UNSIGNED_INT, (void*)mapOffset);


    }
}

if (tile->quadrant_z == nullptr)
{
    HeightMap hp = tile->quadrantZ;
    if (CornersInFrustum(hp.Corners))
    {
        int mapOffset = tile->quadrantZ.index * 6 * heightMapSize*heightMapSize * sizeof(unsigned int);
        glDrawElements(drawMode, 6 * heightMapSize*heightMapSize, GL_UNSIGNED_INT, (void*)mapOffset);
    }


}

if (tile->quadrant_w == nullptr)
{
    HeightMap hp = tile->quadrantW;
    if (CornersInFrustum(hp.Corners))
    {
        int mapOffset = tile->quadrantW.index * 6 * heightMapSize*heightMapSize * sizeof(unsigned int);
        glDrawElements(drawMode, 6 * heightMapSize*heightMapSize, GL_UNSIGNED_INT, (void*)mapOffset);
    }


}

顶点着色器：

#version 430 //core
layout(location = 0) in vec4 vertexPosition_modelspace;
layout(location = 2) in vec4 vertexNormal_modelspace;

layout(std430, binding = 4) buffer PerFrame
{
    mat4 ViewMatrix;
    vec4 CameraPosition;
    vec4 CameraForward;
    mat4 ModelMatrix;
    float time;
    float perFrametab[3];
};

layout(std430, binding = 5) buffer Constant
{
    mat4 ProjectionMatrix;
    vec4 SeedBuffer;
    vec2 screenSize;
};
layout( std430, binding=10 ) buffer DebugBuffer
{
    vec4 debug; 
};


out vec3 Position_worldspace;
out vec3 Normal_cameraspace;
out vec3 EyeDirection_cameraspace;
out vec3 LightDirection_cameraspace;
out vec3 LightPosition_worldspace;
out vec3 NormalWorldSpace;

void main()
{
gl_Position =ProjectionMatrix*
ViewMatrix*ModelMatrix*
vec4(vertexPosition_modelspace.xyz,1);

float C = 1,
near = 0.1,
far = 10000000.0f;
gl_Position.z = (2*log2(C*gl_Position.w + 1) / log2(C*far + 1) - 1) * gl_Position.w;
Position_worldspace = (ModelMatrix*vec4(vertexPosition_modelspace.xyz,1)).xyz;
Normal_cameraspace = ( ViewMatrix *(vec4(vertexNormal_modelspace.xyz,0))).xyz; 
vec4 normalTemp=ModelMatrix*vertexNormal_modelspace;
NormalWorldSpace=normalize(normalTemp.xyz);
}
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1 回答 1

1

好的，我找到了解决方案。问题出在计算着色器中的 imageStore() 和 imageLoad() 中。即使我将 image2D 用于存储目的，我也需要添加

glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);

生成纹理后。这就是 ATI 和 nVidia 之间的区别。

于 2017-09-13T14:23:25.237 回答