How to best colourise an object when touched

Questions
1

Button type things in most applications look best when they change colour or tone (and make a sound like a click - thats the easy bit I think) when they are touched, particularly while they are touched - to make it look like they really have been depressed as a real button. My question is how best to do this in Codea. If I use a rectangle or ellipse how can apply a colour change only to the touched shape. If I use a sprite am I best make a copy of the sprite in two different colour schemes.

2

If your using a sprite maybe tint() will save the use of a second sprite

3

^ Ditto ^

4

Thanks, that maybe of help.

5

I really don’t get it. Why aren’t commands such as fill() and tint() applied to specific things? Why do they have to be applied universally?

6

To be specific try

pushstyle()
tint()
fill()
rect()
popstyle()

Using the values you prefer

7

@mattbastin it’s a state-driven environment. You can wrap these things up into objects, if you like. For example, here is a rectangle class that maintains its style and transform as a state:

Rectangle = class()

function Rectangle:init( x, y, w, h )
    self.pos = vec2(x,y)
    self.size = vec2(w,h)

    self.fill = color( 255, 255, 255 )
    self.stroke = color( 0, 0, 0, 0 )
    self.strokeWidth = 0
end

function Rectangle:draw()
    pushStyle()

    stroke( self.stroke )
    strokeWidth( self.strokeWidth )
    fill( self.fill )
    rect( self.pos.x, self.pos.y, self.size.x, self.size.y )

    popStyle()
end

You could use it like this:

function setup()
    rect1 = Rectangle( 0, 0, 100, 100 )
    rect1.fill = color( 255, 0, 0 )
    rect1.stroke = color( 255 )
    rect1.strokeWidth = 5

    rect2 = Rectangle( 100, 100, 100, 100 )
    rect2.fill = color( 0, 0, 255 )
end

function draw()
    background(128)

    rect1:draw()
    rect2:draw()
end
8

Thanks very much. I tried the code and with a bit of tweaking with the colours got it to work as I expected ( I mean from reading your code). I feel like I have a lt to learn.