little formula to solve
BlitzMax Forums/BlitzMax Programming/little formula to solve
| ||
| Hi lads, got a method here for my gui slider. Basically we have these numbers to work with: - The Range of the slider. These two variables could be between -1 to 1 or even 0 to 10. This is range1 and range2. They dictate the range of values the slider can have. - The Value of the slider. This variable is a value between the range above. What I want to do is use the two range variables and the value between that range to calculate a final percentage between 0 and 99. How do I do it? |
| ||
| Percentage = ((Value - Range1) * 100) / (Range2 - Range1) |
| ||
Maybe something like this?r = range2-range1 p = ((value-range1)/r)*99 p should now contain a value between 0 and 99 Not 100% sure it works. Didn't test it and I'm really tierd. I also have a cold wich makes it hard to think, sometimes. :P Edity: I was also too slow writing this post. 2nd edit: Heh, removed a small typo in the code. :) |
| ||
| Haha! I saw that first version :) |
| ||
| Hic |
| ||
| The reason why the formulas above don't work is because they don't deal with a situation like -1 to 1 where the value is actually 0... The problem is when you have a range of -1 to 1 and the value is 0... (in the middle) you multiply that by 100 and get 0 instead of the correct value of 50 Now can you see the problem with it? |
| ||
| Mine and Deps do work. Mine is slightly better since it would still work well with Ints. Your example: Percentage = ((Value - Range1) * 100) / (Range2 - Range1) Percentage = (( 0 - -1 ) * 100) / ( 1 - -1 ) Percentage = (( 1 ) * 100) / ( 2 ) Percentage = 100 / 2 Percentage = 50 |
| ||
Offset = 0 - Range1 SValue = Value + Offset Percent = SValue * 100 / (Range2 - Range1) I think will work. |
| ||
| That does exactly the same: SValue is the same as (Value - Range1) |
| ||
| Ha, shaken off the hangover, here you are : Two functions, One will return the value at a given percentage of the slider. The other will return the percentage value of the slider for a given value. For Local a = 0 To 99 Print SliderValue(-2.0,4.0,a) Next Function SliderValue:Float(Range1:Float,Range2:Float,SliderValue:Float) Return (SliderValue * ((Range2 - Range1) / 100)) + Range1 End Function Function SliderPercentage:Float(Range1:Float,Range2:Float,ActualValue:Float) Return (ActualValue - Range1) / ((Range2 - Range1) / 100) End Function |
| ||
| Thanks a lot :D Much appreciated everyone. |
   |