C++ OpenGL纹理未使用提供的UV坐标正确环绕对象

我试图让纹理在OpenGL中正常工作

现在的问题是：

如您所见，图像位于每个三角形的各个面上，而不是整个网格周围

我希望纹理正常工作：即：环绕整个网格，而不是每个三角形。

进一步说明问题；我创建了模型的线框，并将各个点加载到“文本转储”中，以便您可以看到映射应如何工作：

上述模型的顶点/法线/UV 上面图像的纹理

代码清单 正在加载图像： 下面是我如何在中加载图像（部分代码列表）：

绑定属性并加载到GPU 下面是我如何绑定各种属性并将数据发送到GPU：

glGenVertexArrays(1, &Pointer_VAO);
glBindVertexArray(Pointer_VAO);

glGenBuffers(1, &Vertex_VBO);

glBindBuffer(GL_ARRAY_BUFFER, Vertex_VBO);

glBufferData(GL_ARRAY_BUFFER, TotalBufferSize, NULL, GL_STATIC_DRAW);

glBufferSubData(GL_ARRAY_BUFFER, NULL, VerticesBufferSize, Vertices);

glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 0, 0);
glEnableVertexAttribArray(0);

if (HasNormals) {
    glBufferSubData(GL_ARRAY_BUFFER, NormalOffset, NormalBufferSize, Normals);
    /*
    Set up our Attribute pointer so that our Shader knows where to get our normals.
    */
    glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 0, 0);
    glEnableVertexAttribArray(1);
}

if (HasUVs) {
    glBufferSubData(GL_ARRAY_BUFFER, UVOffset, UVBufferSize, UVs);
    glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, 0, 0);
    glEnableVertexAttribArray(2);
}

glGenBuffers(1, &MVP_VBO);
glBindBuffer(GL_ARRAY_BUFFER, MVP_VBO);
glBufferData(GL_ARRAY_BUFFER, ModelMatrixInstances.size() * sizeof(glm::mat4), NULL, GL_DYNAMIC_DRAW);
glVertexAttribPointer(3, 4, GL_FLOAT, GL_FALSE, sizeof(glm::mat4), (void*)(sizeof(GLfloat) * 0));
glEnableVertexAttribArray(3);
glVertexAttribDivisor(3, 1);
glVertexAttribPointer(4, 4, GL_FLOAT, GL_FALSE, sizeof(glm::mat4), (void*)(sizeof(GLfloat) * 4));
glEnableVertexAttribArray(4);
glVertexAttribDivisor(4, 1);
glVertexAttribPointer(5, 4, GL_FLOAT, GL_FALSE, sizeof(glm::mat4), (void*)(sizeof(GLfloat) * 8));
glEnableVertexAttribArray(5);
glVertexAttribDivisor(5, 1);
glVertexAttribPointer(6, 4, GL_FLOAT, GL_FALSE, sizeof(glm::mat4), (void*)(sizeof(GLfloat) * 12));
glEnableVertexAttribArray(6);
glVertexAttribDivisor(6, 1);

glGenBuffers(1, &NormalMatrix_VBO);
glBindBuffer(GL_ARRAY_BUFFER, NormalMatrix_VBO);
glBufferData(GL_ARRAY_BUFFER, ModelMatrixInstances.size() * sizeof(glm::mat3), NULL, GL_DYNAMIC_DRAW);
glVertexAttribPointer(7, 3, GL_FLOAT, GL_FALSE, sizeof(glm::mat3), (void*)(sizeof(GLfloat) * 0));
glEnableVertexAttribArray(7);
glVertexAttribDivisor(7, 1);
glVertexAttribPointer(8, 3, GL_FLOAT, GL_FALSE, sizeof(glm::mat3), (void*)(sizeof(GLfloat) * 3));
glEnableVertexAttribArray(8);
glVertexAttribDivisor(8, 1);
glVertexAttribPointer(9, 3, GL_FLOAT, GL_FALSE, sizeof(glm::mat3), (void*)(sizeof(GLfloat) * 6));
glEnableVertexAttribArray(9);
glVertexAttribDivisor(9, 1);

glGenBuffers(1, &Index_VBO);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, Index_VBO);

glBufferData(GL_ELEMENT_ARRAY_BUFFER, TotalPolygonCount * 3 * sizeof(unsigned int), Indices, GL_STATIC_DRAW);

glBindVertexArray(0); 

着色器 顶点着色器：

#version 430

layout(location = 0) in vec3 vPosition;
layout(location = 1) in vec3 vNormal;
layout(location = 2) in vec2 vUV;
layout(location = 3) in mat4 ModelViewProjectionMatrix;
layout(location = 7) in mat3 NormalMatrix;

out vec3 SurfaceNormal;
out vec2 TextureCoordinates;

void main () {
    SurfaceNormal = normalize(NormalMatrix * vNormal);
    TextureCoordinates = vUV;
    gl_Position = ModelViewProjectionMatrix * vec4(vPosition, 1.0);
}

片段着色器：

#version 430

uniform MaterialBlock
{
    vec4    MaterialColor;
    vec4    AmbientMeshColor;
    vec4    EmmissiveMeshColor;
    vec4    DiffuseMeshColor;
    vec4    SpecularMeshColor;
    float   MeshShininess;
    float   ObjectHasMaterialFile;
} Material;

uniform float   EnableWireframe;
uniform vec4    WireframeColor;

uniform float   IfEnableMaterial;

uniform float   EnableLighting;
uniform float   EnableSun;

uniform vec3    SunDirection;
uniform vec3    LightHalfVector;
uniform vec4    SunColor;
uniform vec4    SunSpotCutoff;
uniform float   SunlightStrength;

in vec3 SurfaceNormal;
in vec2 TextureCoordinates;

uniform sampler2D MainTextureSampler;


out vec4 finalColor;

void SunlightWithMaterials() {

    vec4 MaterialTextureColor = texture2D(MainTextureSampler, TextureCoordinates);

    float DiffuseValue = max(0.0, dot(SurfaceNormal, SunDirection));
    float SpecularValue = max(0.0, dot(SurfaceNormal, LightHalfVector));
    if (DiffuseValue == 0.0) {
        SpecularValue = 0.0;
    } else {
        SpecularValue = pow(SpecularValue, Material.MeshShininess);
    }
    vec3 ScatteredLight = Material.AmbientMeshColor.rgb + (SunColor.rgb * DiffuseValue);
    vec3 ReflectedLight = SunColor.rgb * SpecularValue * SunlightStrength;
    vec3 CalculatedColor = min(MaterialTextureColor.rgb * ScatteredLight + ReflectedLight, vec3(1.0));
    finalColor = vec4(CalculatedColor, Material.MaterialColor.a);
}

void SunlightWithoutMaterials() {

    float DiffuseValue = max(0.0, dot(SurfaceNormal, SunDirection));
    float SpecularValue = max(0.0, dot(SurfaceNormal, LightHalfVector));
    if (DiffuseValue == 0.0) {
        SpecularValue = 0.0;
    } else {
        SpecularValue = pow(SpecularValue, Material.MeshShininess);
    }
    vec3 ScatteredLight = Material.AmbientMeshColor.rgb + (SunColor.rgb * DiffuseValue);
    vec3 ReflectedLight = SunColor.rgb * SpecularValue * SunlightStrength;
    vec3 CalculatedColor = min(Material.MaterialColor.rgb * ScatteredLight + ReflectedLight, vec3(1.0));
    finalColor = vec4(CalculatedColor, Material.MaterialColor.a);

    }

void main()
{
    if (EnableWireframe == 1) {
        finalColor = WireframeColor;
    } else {
        if (IfEnableMaterial == 1.0 && ObjectHasMaterialFile == 1.0) {
            if (EnableLighting == 1.0) {
                if (EnableSun == 1.0) {
                    SunlightWithMaterials();
                } 
                else {
                    vec4 MaterialTextureColor = texture2D(MainTextureSampler, TextureCoordinates);
                    finalColor = min(MaterialTextureColor * Material.AmbientMeshColor, vec4(1.0));
                }
            } 
            else {
                vec4 MaterialTextureColor = texture2D(MainTextureSampler, TextureCoordinates);
                finalColor = MaterialTextureColor;
            }
        }
        else {
            if (EnableLighting == 1.0) {
                if (EnableSun == 1.0) {
                    SunlightWithoutMaterials();
                } 
                else {
                    finalColor = min(Material.MaterialColor * Material.AmbientMeshColor, vec4(1.0));
                }
            } else {
                finalColor = Material.MaterialColor;
            }
        }
    }
}

在OpenGL中绘制图像：

glBindVertexArray（指针）；
对于（int i=0；iGetViewMatrix（）*ModelMatrixinStations[i]；
glm:：mat3 NormalMatrix=glm:：transpose（glm:：inverse（glm:：mat3（ModelViewMatrix））；
glm:：mat4 ModelViewProjectionMatrix=CurrentOpenGLController->GetProjectionViewMatrix（）*ModelMatrixinStations[i]；
glBindBuffer（GL_数组_BUFFER，MVP_VBO）；
glBufferSubData（GL_ARRAY_BUFFER，（i*（sizeof（glm:：mat4））），sizeof（glm:：mat4），glm:：value_ptr（ModelViewProjectionMatrix））；
glBindBuffer（GL_数组_BUFFER，NormalMatrix_VBO）；
glBufferSubData（GL_数组_BUFFER，（i*（sizeof（glm:：mat3））），sizeof（glm:：mat3），glm:：value_ptr（NormalMatrix））；
}
if（材质[0]。HasMaterialFile==true）{
GLfloat ObjectHasMaterial=1.0f；
glUniform1fv（CurrentOpenGLController->GetObjectHasMaterialFileID（），1，&ObjectHasMaterial）；
glUniform1i（CurrentOpenGLController->GetMainTextureID（），1）；
材质[0]，纹理（1）；
}
否则{
glBindTexture（GL_TEXTURE_2D，空）；
}
glBufferData（GL_统一_缓冲区，sizeof（材质[0]。颜色属性），材质[0]。颜色属性，GL_动态_绘制）；
GLDRAILEMENTSINCED（GLU三角形、总顶点计数、，
GL_UNSIGNED_INT，NULL，NumberOfChildItems+1）；
if（材质[0]。HasMaterialFile==true）{
glActiveTexture（空）；
glBindTexture（GL_TEXTURE_2D，空）；
}

我们来看看这个

Vertex:  X: -1 Y: 1 Z: 1 Normal:  X: 2.38419e-007 Y: 1 Z: 1.63913e-007 UV Point:  S: 0.333333 T: 0.666667
Vertex:  X: 1 Y: 1 Z: -1 Normal:  X: 2.38419e-007 Y: 1 Z: 1.63913e-007 UV Point:  S: 0.666667 T: 0.333333
Vertex:  X: -1 Y: 1 Z: -1 Normal:  X: 2.38419e-007 Y: 1 Z: 1.63913e-007 UV Point:  S: 0.666667 T: 0.666667
Vertex:  X: 1 Y: 1 Z: -1 Normal:  X: 2.38419e-007 Y: 1 Z: 1.63913e-007 UV Point:  S: 0.666667 T: 0.333333
Vertex:  X: -1 Y: 1 Z: 1 Normal:  X: 2.38419e-007 Y: 1 Z: 1.63913e-007 UV Point:  S: 0.333333 T: 0.666667
Vertex:  X: 1 Y: 0.999999 Z: 1 Normal:  X: 2.38419e-007 Y: 1 Z: 1.63913e-007 UV Point:  S: 0.333333 T: 0.333333

把它浓缩一点

    X  Z       s [1/3] t
 A -1  1 (SW)  1       2 
 B  1 -1 (NE)  2       1 
 C -1 -1 (NW)  2       2
 B  1 -1 (NE)  2       1 
 A -1  1 (SW)  1       2
 D  1  1 (SE)  1       1

现在取细分中重复的点-A和B，即西南和东北

假设s从西向东生长，因此t从北向南生长

因此，西北部的aka C应位于st=（1,1），东南部的aka D应位于st=（2,2）

---

但事实并非如此。它们被交换了

谢谢；我尝试在我的加载代码中交换S和T，但都没有用。作为一项故障排除措施，我将最终颜色设置为纹理坐标以可视化问题：。交换所有S和T只会将问题旋转90度。在我的示例中，您必须将STs交换为相应的点，如C和D

glBindVertexArray(Pointer_VAO);

for (int i = 0; i < ModelMatrixInstances.size(); i++) {
    glm::mat4 ModelViewMatrix = CurrentOpenGLController->GetViewMatrix() * ModelMatrixInstances[i];
    glm::mat3 NormalMatrix = glm::transpose(glm::inverse(glm::mat3(ModelViewMatrix)));
    glm::mat4 ModelViewProjectionMatrix = CurrentOpenGLController->GetProjectionViewMatrix() * ModelMatrixInstances[i];
    glBindBuffer(GL_ARRAY_BUFFER, MVP_VBO);
    glBufferSubData(GL_ARRAY_BUFFER, (i * (sizeof(glm::mat4))), sizeof(glm::mat4), glm::value_ptr(ModelViewProjectionMatrix));
    glBindBuffer(GL_ARRAY_BUFFER, NormalMatrix_VBO);
    glBufferSubData(GL_ARRAY_BUFFER, (i * (sizeof(glm::mat3))), sizeof(glm::mat3), glm::value_ptr(NormalMatrix));
}

if (Materials[0].HasMaterialFile == true) {
    GLfloat ObjectHasMaterial = 1.0f;
    glUniform1fv(CurrentOpenGLController->GetObjectHasMaterialFileID(), 1, &ObjectHasMaterial);
    glUniform1i(CurrentOpenGLController->GetMainTextureID(), 1);
    Materials[0].bindTexture(1);
}
else {
    glBindTexture(GL_TEXTURE_2D, NULL);
}

glBufferData(GL_UNIFORM_BUFFER, sizeof(Materials[0].ColorProperties), Materials[0].ColorProperties, GL_DYNAMIC_DRAW);

glDrawElementsInstanced(GL_TRIANGLES, TotalVertexCount, 
    GL_UNSIGNED_INT,  NULL, NumberOfChildItems + 1);

if (Materials[0].HasMaterialFile == true) {
    glActiveTexture(NULL);
    glBindTexture(GL_TEXTURE_2D, NULL);
}

Vertex:  X: -1 Y: 1 Z: 1 Normal:  X: 2.38419e-007 Y: 1 Z: 1.63913e-007 UV Point:  S: 0.333333 T: 0.666667
Vertex:  X: 1 Y: 1 Z: -1 Normal:  X: 2.38419e-007 Y: 1 Z: 1.63913e-007 UV Point:  S: 0.666667 T: 0.333333
Vertex:  X: -1 Y: 1 Z: -1 Normal:  X: 2.38419e-007 Y: 1 Z: 1.63913e-007 UV Point:  S: 0.666667 T: 0.666667
Vertex:  X: 1 Y: 1 Z: -1 Normal:  X: 2.38419e-007 Y: 1 Z: 1.63913e-007 UV Point:  S: 0.666667 T: 0.333333
Vertex:  X: -1 Y: 1 Z: 1 Normal:  X: 2.38419e-007 Y: 1 Z: 1.63913e-007 UV Point:  S: 0.333333 T: 0.666667
Vertex:  X: 1 Y: 0.999999 Z: 1 Normal:  X: 2.38419e-007 Y: 1 Z: 1.63913e-007 UV Point:  S: 0.333333 T: 0.333333

    X  Z       s [1/3] t
 A -1  1 (SW)  1       2 
 B  1 -1 (NE)  2       1 
 C -1 -1 (NW)  2       2
 B  1 -1 (NE)  2       1 
 A -1  1 (SW)  1       2
 D  1  1 (SE)  1       1