Image thumbnails are not working

[kiptunor]

I defied the USE_THUMBNAILS macro and no image is showing when switching to thumbnail list

[aiekick]

Hello,

did you defined the functions for create/destroy the gpus textures ?

you can check the documenatation or the demo app.

(by ex for opengl)

ImGuiFileDialog::Instance()->SetCreateThumbnailCallback([](IGFD_Thumbnail_Info* vThumbnail_Info) -> void {
    if (vThumbnail_Info && vThumbnail_Info->isReadyToUpload && vThumbnail_Info->textureFileDatas) {
        GLuint textureId = 0;
        glGenTextures(1, &textureId);
        vThumbnail_Info->textureID = (void*)(size_t)textureId;

        glBindTexture(GL_TEXTURE_2D, textureId);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, (GLsizei)vThumbnail_Info->textureWidth, (GLsizei)vThumbnail_Info->textureHeight, 0, GL_RGBA, GL_UNSIGNED_BYTE, vThumbnail_Info->textureFileDatas);
        glFinish();
        glBindTexture(GL_TEXTURE_2D, 0);

        delete[] vThumbnail_Info->textureFileDatas;
        vThumbnail_Info->textureFileDatas = nullptr;

        vThumbnail_Info->isReadyToUpload  = false;
        vThumbnail_Info->isReadyToDisplay = true;
    }
});
ImGuiFileDialog::Instance()->SetDestroyThumbnailCallback([](IGFD_Thumbnail_Info* vThumbnail_Info) {
    if (vThumbnail_Info) {
        auto texID = (GLuint)(size_t)vThumbnail_Info->textureID;
        glDeleteTextures(1, &texID);
        glFinish();
    }
});