[unity shader] substitution of bool type in the property definition

stay shader Of Properties Attribute definition , Can't use bool Type variable , The following wording will report an error .

_IsTrue("Istrue", bool) = true

have access to float type +toggle Label instead of

[Toggle(_True)]_IsTrue("Istrue", float) = 1

increase Toggle After label , stay Inspector The palette , This variable is a check box .

If checked, it will be the default value , Unchecking is not the default .

Where judgment is needed , Judge _IsTrue Whether it is the default value .