message: Default A8 textures to show the alpha channel only
diff: @@ -1571,6 +1571,15 @@ void TextureViewer::UI_OnTextureSelectionChanged(bool newdraw)
  ui->channelBlue->setChecked(true);
  ui->channelAlpha->setChecked(false);
  + // for alpha textures, only show the alpha channel
  + if(texptr->format.type == ResourceFormatType::A8)
  + {
  + ui->channelRed->setChecked(false);
  + ui->channelGreen->setChecked(false);
  + ui->channelBlue->setChecked(false);
  + ui->channelAlpha->setChecked(true);
  + }
  +
  ui->depthDisplay->setChecked(true);
  ui->stencilDisplay->setChecked(false);
  