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Accurately Converting NSString to GLFloat - iPhone

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By User



Say I have some vertice values which I am reading into my app as a NSString :





-7501.6 -6198.2 834.939 -5547.66 -6348.32 2122.65





The values in the source are always 6 figures in length.





I need to pass these exact values to OpenGL. If I try to cast as a float (using NSString floatValue) then, as expected, I get an approximate value for each float due to the inexact nature of a float :





-7501.600098, -6198.200195, 834.939026 -5547.660156, -6348.319824, 2122.649902





Can anyone suggest a way that I can get these values into OpenGL and retain their exact initial integrity ?





Thank you.


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Comments

  1. Tips For AllFebruary 21, 2012 at 2:13 PM

    See 'Getting Numeric Values' paragraph from NSString Documentation (Apple).

    [str floatValue];
    [str doubleValue];

    ReplyDelete
  2. Tips For AllFebruary 21, 2012 at 2:13 PM

    maybe this: NSString to NSNumber could help.

    ReplyDelete

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