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copied!<p>I see this question is tagged Unity3D.</p> <p>Is it possible that <code>f</code> is a public variable exposing it to be modified in the Unity Editor? If so, any value set in the editor will override a value set in the code during variable declaration. The value set during declaration is simply used as a default value for the Unity Editor.</p> <p>If this is the case then someone could have set <code>f</code> to 0 in the editor causing it to be 0 when you do your math.</p> <hr> <p><strong>Edited Answer After Some Testing: 8/22/2013</strong></p> <p>I was able to repeat your problem when using Unity. It seems there is a bug in Unity that doesn't allow variables to be used during initialization of an array at declaration. Everything works properly if it is a standard C# project, however, so this is related to Unity only.</p> <p>The problem has nothing to do with <code>f</code> being <code>static</code> or <code>readonly</code>, only that it is a variable. The following code does not work:</p> <pre><code>public void init() { float f = 1.25f; float[,] FLIPPER_CENTERS = new float[,] { { (5+f), (27*f) }, { 30 - (20*f), (27*f)}, { (6*f), (25*f) }, { 20 - (6*f), (25*f) }, { (8), (15)}, { (10 - 8), (15)}, { (8), (20)}, { (67 - 8), (20)}, }; Debug.Log(FLIPPER_CENTERS[0,0]); // Outputs 0 | Expected 6.25f } </code></pre> <p>Anywhere the variable <code>f</code> is used in the array initialization will result in a 0. More specifically, it doesn't just set <code>f = 0</code> it sets the whole expression to 0. For example, the first element in the array above, <code>5+f</code>, would result in 0 - not 5. The elements with constants, however, evaluate normally (such as the last few elements). It seems if Unity is bailing out of the evaluation when it encounters a variable.</p> <p>If, however, I define the array in one line and then set the elements later everything works normally. For example:</p> <pre><code>public void init() { float f = 1.25f; float[,] FLIPPER_CENTERS = new float[8, 2]; FLIPPER_CENTERS[0, 0] = 20*f; FLIPPER_CENTERS[0, 1] = 27*f; FLIPPER_CENTERS[1, 0] = 30 - (20*f); FLIPPER_CENTERS[1, 1] = 27*f; FLIPPER_CENTERS[2, 0] = 6*f; FLIPPER_CENTERS[2, 1] = 25*f; FLIPPER_CENTERS[3, 0] = 20 - (6*f); FLIPPER_CENTERS[3, 1] = 25*f; FLIPPER_CENTERS[4, 0] = 8; FLIPPER_CENTERS[4, 1] = 15; FLIPPER_CENTERS[5, 0] = 10 - 8; FLIPPER_CENTERS[5, 1] = 15; FLIPPER_CENTERS[6, 0] = 8; FLIPPER_CENTERS[6, 1] = 20; FLIPPER_CENTERS[7, 0] = 67 - 8; FLIPPER_CENTERS[7, 1] = 20; Debug.Log(FLIPPER_CENTERS[0,0]); // Outputs 25.0f | Expected 25.0f } </code></pre> <p>Just did some further testing and it seems that the problem is only present with multidimensional arrays. The following gives expected output:</p> <pre><code>public void init() { float f = 1.25f; float[] FLIPPER_CENTERS = new float[] { (f), (f * 2), (f * 3), (f * 4), (f + 1), (f + 2), (f + 3), (f + 5) }; Debug.Log(FLIPPER_CENTERS[0]); // Outputs 1.25f | Expected 1.25f } </code></pre> <p>This certainly seems like a bug in Unity to me. It is generally recommended, however, that <code>const</code> be used over <code>static readonly</code>. Using <code>const</code> provides a performance benefit (albeit slight) since it is converted into a literal at compile time. In addition, using <code>const</code> will avoid this problem altogether.</p> <p>I know you already figured out <code>const</code> works, just wanted to give you a little information that I discovered.</p>

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