Complex coding for Backlights

[Mikemike]

Getting closer =) I changed a few minor things like, fill color, image size, encoder properties and the initial opacity. It's set for initial transparent, but when I turn the rotary encoder, it goes straight to fully filled black and then slowly brightens up but not a huge deal. I'll keep playing with the code some.

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my_canvas=canvas_add(-50,-50,575,575)

---lets draw the inital black box
canvas_draw(my_canvas, function()
_rect(40,40,575,575)
_fill("black",0) --Note the 0 after the "black". It is the opacity
end)

---now lets dim the black box

--create a var for dimming/opacity
dim_var=1
--Add a function
function dim_my_canvas()
canvas_draw(my_canvas, function()
_rect(40,40,575,575)
_fill("black",dim_var) ---Note we have used the var we created vary the opacity
end)
end

---add your dial
function dial_change(dir)
dim_var=dim_var+(dir*0.1) ---Change the opacity value
var_cap(dim_var,0,1) ---Limit the scope of the opacity value.
dim_my_canvas () --force a callback to the dim function
end

-- Create a new rotary encoder
hw_dial_add("ARDUINO_MEGA2560_A_D3", "ARDUINO_MEGA2560_A_D4","TYPE_1_DETENT_PER_PULSE", dial_change)



[JackZ]

Hmm I don’t know. Wouldn’t it be better to use opacity(), instead of redrawing the black rectangle every time?
Untested, but I guess that this function would work as well.

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function dim_my_canvas()

  opacity(my_canvas,dim_var)

end

And now that the function is stripped down to only one line, this instruction could probably better by being off directly incorporated into the calling function dial_change(dir) to save execution time and make the code easier to read.

Another remark: setting the initial value of dim_var to 1 is what makes the backlight jump to black

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 dim_var=1

The initial value should be 0 to reflect the initial state of your black rectangle that you set to 0 (transparent) when you created it.
So using dim_var while creating the initial rectangle is the best solution to ensure consistency.

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 fill("black",dim_var)

.
Of course, in that case

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dim_var=0

should be placed at the very beginning of your code instead of line 23, to avoid Lua throwing an error

Jacques

[Mikemike]

Hmm I don’t know. Wouldn’t it be better to use opacity(), instead of redrawing the black rectangle every time?
Untested, but I guess that this function would work as well.

Code: Select all

  
function dim_my_canvas()

  opacity(my_canvas,dim_var)

end

And now that the function is stripped down to only one line, this instruction could probably better by being off directly incorporated into the calling function dial_change(dir) to save execution time and make the code easier to read.

Jacques

Probably, but I'm not truly understanding all this yet as I'm in a huge learning curve and it's a slow go. It does make sense to me that the less is better to produce the same result.

Mikemike

[JackZ]

No worries, we are here to help. Everybody went through this route!

[Mikemike]

No worries, we are here to help. Everybody went through this route!

Thank you.