How to prevent 'control' from being seen when I trigger '^WheelUp'

I have this painting programme, when you hold down control the move tool temporarily becomes the active tool.

I am trying to create two hotkeys that will increase decrease brush size:

#SingleInstance, force
^wheelup::
    tooltip, Ctrl + WheelUp
    ;Sendinput, {[}                     ;Increase brush size
    return
^wheeldown::
    tooltip, Ctrl + Wheeldown
    ;Sendinput, {]}                     ;Reduce brush size
    return

I am using a the tooltip command to demonstrate my issue.

But the programme notices that control key is held/pressed, and so makes the move tool the active tool, thus making it impossible to change the brush size. This recording shows what I mean

I tried applying the $ prefix but the programme still sees control and switches to the move tool:

#SingleInstance, force
$^wheelup::
    tooltip, Ctrl + WheelUp
    ;Sendinput, {[}                     ;Increase brush size
    return
$^wheeldown::
    tooltip, Ctrl + Wheeldown
    ;Sendinput, {]}                     ;Reduce brush size
    return

Is there a way to get AHK to "hide" the pressing or holding of control from the painting programme?

Solution

You can disable one of the Control keys in this program and use the other Control key to activate the move tool:

#Requires AutoHotkey v1.1

#IfWinActive ahk_exe program.exe

    ; disable the left Control key in this program 
    LCtrl::return

    ; left Control + wheel
    <^wheelup:: tooltip Ctrl + WheelUp
    <^wheeldown:: tooltip Ctrl + Wheeldown

#IfWinActive ; turn off context sensitivity

Replace program.exe with the ahk_exe of your program.