Question

我正在尝试将纹理应用于opengl中的基本三角形。问题是我的纹理不起作用，它仅将奇怪的颜色应用于三角形...

我已经看过该文档以及一些youtube教程，但我确实无法使其正常工作。

以下是一些代码示例：

纹理构造函数-

Textures::Textures(const std::string& fileName)
{

int width, height, numComponents;
unsigned char * data = stbi_load(
                            fileName.c_str()
                            , &width
                            , &height
                            , &numComponents
                            , 0
                          );

if (data == NULL)
    std::cerr << "Texture loading error: " << fileName << std::endl;

glGenTextures(1, &m_texture);
glBindTexture(GL_TEXTURE_2D, m_texture);

glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);

glPixelStorei(GL_UNPACK_ALIGNMENT, 1);

if (numComponents == 3)
    glTexImage2D(
        GL_TEXTURE_2D
        , 0
        , GL_RGB
        , width
        , height
        , 0
        , GL_RGB
        , GL_UNSIGNED_BYTE
        , data
    );
else if(numComponents == 4)
    glTexImage2D(
        GL_TEXTURE_2D
        , 0
        , GL_RGBA
        , width
        , height
        , 0
        , GL_RGBA
        , GL_UNSIGNED_BYTE
        , data
    );

glBindTexture(GL_TEXTURE_2D, 0);

stbi_image_free(data);

}

Mesh构造函数-

Meshes::Meshes(Vertex* vertices, unsigned int numVertices)
{

m_drawCount = numVertices;

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

std::vector<glm::vec3> positions;
std::vector<glm::vec2> texCoord;

positions.reserve(numVertices);
texCoord.reserve(numVertices);

for (unsigned int i = 0; i < numVertices; ++i) {

    positions.push_back( *vertices[i].getPos() );
    texCoord.push_back( *vertices[i].getTexture() );

}

glGenBuffers(NUM_BUFFERS, m_vertexArrayBuffers);
glBindBuffer(GL_ARRAY_BUFFER, m_vertexArrayBuffers[POSITION_VB]);
glBufferData(
                GL_ARRAY_BUFFER
                , positions.size() * sizeof(positions[0])
                , &positions[0]
                , GL_STATIC_DRAW
            );

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

glBindBuffer(GL_ARRAY_BUFFER, m_vertexArrayBuffers[TEXTURE_COORD_VB]);
glBufferData(
    GL_ARRAY_BUFFER
    , texCoord.size() * sizeof(texCoord[0])
    , &texCoord[0]
    , GL_STATIC_DRAW
);

glEnableVertexAttribArray(1);
glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 0, 0);

glBindVertexArray(0);

}

着色器片段-

#version 120

varying out vec4 diffuseColor;

varying vec2 texCoord0;

uniform sampler2D diffuse;

void main()
{

diffuseColor = texture2D(diffuse, texCoord0 );

}

着色器顶点-

#version 120

attribute vec3 position;
attribute vec2 texCoord;

varying vec2 texCoord0;

void main()
{

gl_Position.xyz = position;
gl_Position.w = 1;
texCoord0 = texCoord;

}

以下是github上的代码，因此您可以自己检查：https://github.com/Kosta-Git/Pong/tree/master/Pong

我还有另一个问题，就是我什至无法加载texture.jpg文件（bricks.jpg可以工作），但我想这是由于它不是512x512。

Answer 1

问题出在Shaders类的构造函数中。着色器程序未正确链接，因为m_shaders[0]设置了两次，但从未设置m_shaders[1]。

OpenGL / Glew C ++纹理不适用

1 个答案: