J3MD Defines and conditional mappings

Troubleshooting graphics
1

When a define mapped parameter is “set”, the shader gets recompiled only if the value has changed. So if we have:

MaterialDef TeamBar {

    MaterialParameters {
        Float param1
    }

    Technique {
        ...
        Defines {
            PARAM1_IS_SET : param1
        }
    }
}

The shader will be compiled whenever the param1 changes it value instead of just being compiled if the param is set/removed.

So my question is: is it possible to do it work like?:

MaterialDef TeamBar {

    MaterialParameters {
        Float param1
    }

    Technique {
        ...
        Defines {
            PARAM1_IS_SET : param1 != 0
        }
    }
}

So the shader only gets compiled if the condition (PARAM1_IS_SET) changes it value (being this one based on if the param param1 is != 0)?

2

You can’t no. The mechanism hasn’t been thought like this.