How to Convert an int slider to a toggle checkbox

[rachid]

I'm trying to share osl shaders for all DCC about 97 osl shaders
but I need some help to convert a int slider to a toggle checkbox(boolean) in mtd file.
here is an example to load a texture
[attr Add]  
    houdini.label       STRING "Add"
    houdini.type         STRING "file:image"
    houdini.callback     STRING "python:import htoa.texture; htoa.texture.imageFilenameCallback()"    
This create a button to load texture

Here is an example for popup menu
[attr Coordspace]    
    houdini.type     STRING     "menu:replace:menu"
    houdini.menu     STRING     "world;world;object;object;camera;camera;shader;shader;screen;screen;NDC;NDC"
This create popup menu with  :world, object, camera, shader, screen, NDC    

How can I convert a slider to a toggle checkbox for this:

[attr AutoGamma]
    houdini.label       STRING "Auto Gamma"
    min                 FLOAT     0
    softmax             FLOAT     1

any help will be appreciated