Prepare an array to record the availability of registers to prevent the same register from being disabled more than once.

In the enableAttrib function, when enabling a register, tell the renderer that it is available by using the location number as an argument.

If the registers corresponding to the attributes that are not used for drawing are left open, the data still stored there will cause problems.
So it asks the renderer if the register corresponding to it is open, and if it is, it closes it and notifies the renderer and shader of that state.

Use === instead of ==.

remove trailing space

If the shader doesn't know that the register has been disabled by another shader, it can't enable it.
Therefore, even if the corresponding shader does not know about it, if the register used by it is disabled, enable processing should be performed.

Since only the global array (named "registerEnabled") needs to know the enabled/disabled state of a register,
we eliminate the "enabled" property of attribute.

It is impossible for the shader itself to know when a register is available or not. I decided to leave that to the global array.
So I'm going to remove that property.

I decided to use a global flag to manage the enabled/disabled state of the registers used to store shader attributes.
This value will be true if the geometry supplies a value, false if it does not.
Therefore, I prepared a geometry with aTexCoord and a geometry without it, and tested whether the value was properly switched.

I accidentally wrote "myp5.createVector" as "createVector". Just a typo. Excuse me.