Colour Changer

[ericfourfour]

This program allows you to add a blending colour effect very easily. Here is the source:

code:

class ColourChanger     export set_duration, add_colour, remove_colours, get_colour, was_switched, update     var clr : flexible array 0 .. -1 of int     var clr_bound := -1     var id : array 0 .. 1 of int := init (0, 1)     var current_colour : int     var change_duration := 1000     var start_time := 0     var timer := 0     var switched := false     fcn get_colour () : int         result current_colour     end get_colour     fcn was_switched () : boolean         result switched     end was_switched     proc set_duration (ms : int)         start_time := Time.Elapsed         timer := 0         if ms not= 0 then             change_duration := ms         else             change_duration := 1         end if     end set_duration     proc add_colour (c : int)         clr_bound += 1         new clr, clr_bound         clr (clr_bound) := c     end add_colour     proc remove_colours ()         clr_bound := -1         new clr, clr_bound     end remove_colours     fcn merge (clr1, clr2 : int, fraction : real) : int         var r, b, g : array 0 .. 2 of real         var amount : array 0 .. 1 of real         RGB.GetColour (clr1, r (0), g (0), b (0))         RGB.GetColour (clr2, r (1), g (1), b (1))         amount (0) := 1 - fraction         amount (1) := fraction         r (2) := r (0) * amount (0) + r (1) * amount (1)         g (2) := g (0) * amount (0) + g (1) * amount (1)         b (2) := b (0) * amount (0) + b (1) * amount (1)         result RGB.AddColour (r (2), g (2), b (2))     end merge     proc swith_colours ()         for i : 0 .. 1             id (i) := (id (i) + 1) rem (clr_bound + 1)         end for         switched := true         set_duration (change_duration)     end swith_colours     proc update ()         timer := Time.Elapsed - start_time         var fraction := timer / change_duration         if fraction > 1 then             swith_colours ()         else             switched := false             if clr_bound > 0 then                 current_colour := merge (clr (id (0)), clr (id (1)), fraction)             elsif clr_bound = 0 then                 current_colour := clr (0)             end if         end if     end update end ColourChanger

Here is a program that uses it:

code:

var c : ^ColourChanger new ColourChanger, c c -> set_duration (500) c -> add_colour (red) c -> add_colour (blue) loop     c -> update ()     Draw.FillBox (0, 0, 100, 100, c -> get_colour ())     delay (10) end loop

You can set the duration between colours (how long the transition is). You can also use an unlimited amount of colours. It is fps independent meaning if you set the duration to 1000 milliseconds and your delay is 10 or you delay is 273 it will always be at the next colour after 1000 milliseconds (although 1000 isn't a multiple of 273 so it technically can't reach the next colour. However it would still be at its respective colour in the transition).

To set the duration:

code:

set_duration (ms : int)

To add a colour:

code:

add_colour (c : int)

To remove the colours:

code:

remove_colours ()

To update the object:

code:

update ()

To get the colour:

code:

get_colour () : int

To tell if the colour was switched in the previous update:

code:

was_switched () : boolean

[Hackmaster]

that's nice, eric.

now animate it! move it across the screen! you are halfway to making that flowerbox screensaver for windows!

or, alterativley, make it the whole screen!