Assimp - 如何使用任何文件格式导入带有纹理的网格?

Assimp - How do you import a mesh with textures using any file format?

当我导入网格时,我得到 material,但无法访问纹理的文件名。 .mtl 文件明确显示纹理的文件名。在代码中,它显示纹理计数为 1,但文件名字段显示空字符串,而 fullPath 输出“*0”。在 mTexture 中,它确实显示了纹理文件扩展名“.png”,但没有显示纹理本身的文件名。感谢您的帮助。

    if (scene->HasMaterials())
    {
        for (unsigned int i = 0; i < scene->mNumMaterials; ++i)
        {
            aiMaterial* material = scene->mMaterials[i];
            aiString name;
            material->Get(AI_MATKEY_NAME, name);
            aiReturn texFound = scene->mMaterials[i]->GetTexture(aiTextureType_DIFFUSE, i, &name);

            if (material->GetTextureCount(aiTextureType_DIFFUSE) > 0)
            {
                aiString path;
                if (material->GetTexture(aiTextureType_DIFFUSE, 0, &path, NULL, NULL, NULL, NULL, NULL) == AI_SUCCESS)
                {
                    std::string fullPath = path.data;


                }
            }
        }
    }

这应该可以正常工作。您能否提供 obj-model 及其相应的 material 文件并在此处生成新的问题报告:https://github.com/assimp/assimp/issues

然后我们可以尝试调查您的示例中出了什么问题。

如果有人对我如何解决我的问题感到好奇,如下所示。在 .mtl 文件中,我必须添加 map_Kd diffusefile.png 以添加漫反射文件,以便 assimp 可以获取纹理文件。

        if (scene->HasMaterials())//True when number of materials is greater than 0
        {
            for (unsigned int m = 0; m < scene->mNumMaterials; ++m)
            {
                aiMaterial* material = scene->mMaterials[m];//Get the current material
                aiString materialName;//The name of the material found in mesh file
                aiReturn ret;//Code which says whether loading something has been successful of not

                ret = material->Get(AI_MATKEY_NAME, materialName);//Get the material name (pass by reference)
                if (ret != AI_SUCCESS) materialName = "";//Failed to find material name so makes var empty

                //Diffuse maps
                int numTextures = material->GetTextureCount(aiTextureType_DIFFUSE);//Amount of diffuse textures
                aiString textureName;//Filename of the texture using the aiString assimp structure

                if (numTextures > 0)
                {
                    //Get the file name of the texture by passing the variable by reference again
                    //Second param is 0, which is the first diffuse texture
                    //There can be more diffuse textures but for now we are only interested in the first one
                    ret = material->Get(AI_MATKEY_TEXTURE(aiTextureType_DIFFUSE, 0), textureName);

                    std::string textureType = "diff_";
                    std::string textureFileName = textureType + textureName.data;//The actual name of the texture file
                }
            }