2014-01-30 104 views
0

我正在做一个演示,以将矩阵(3x3)转换为四元数,但是我卡住的东西对大多数来说似乎很简单,但我的大脑正在关闭,因为我已经一直在这工作几个小时。下面的代码使用C++和openGL在我选择的IDE(VS2010 Express)中编译好,但我收到以下错误 - “变量'm11'正在使用而未被初始化。”这个错误出现在我的矩阵中的所有浮点变量,所以当我尝试运行代码时,它只是炸弹出来。谁能帮忙?谢谢矩阵旋转到四元数

代码:

void matrixIntoQuaternions() { 

      // Input matrix 3X3 
      float m11,m12,m13; 
      float m21,m22,m23; 
      float m31,m32,m33; 

      // Output quaternion 
      float w,x,y,z; 
      // Determine which of w,x,y, or z has the largest absolute value 
      float fourWSquaredMinus1 = m11 + m22 + m33; 
      float fourXSquaredMinus1 = m11 - m22 - m33; 
      float fourYSquaredMinus1 = m22 - m11 - m33; 
      float fourZSquaredMinus1 = m33 - m11 - m22; 

      int biggestIndex = 0; 
      float fourBiggestSquaredMinus1 = fourWSquaredMinus1; 

      if(fourXSquaredMinus1 > fourBiggestSquaredMinus1) { 
       fourBiggestSquaredMinus1 = fourXSquaredMinus1; 
       biggestIndex = 1; 
      } 
      if (fourYSquaredMinus1 > fourBiggestSquaredMinus1) { 
       fourBiggestSquaredMinus1 = fourYSquaredMinus1; 
       biggestIndex = 2; 
      } 
      if (fourZSquaredMinus1 > fourBiggestSquaredMinus1) { 
       fourBiggestSquaredMinus1 = fourZSquaredMinus1; 
       biggestIndex = 3; 
      } 
      // Per form square root and division 
      float biggestVal = sqrt (fourBiggestSquaredMinus1 + 1.0f) * 0.5f; 
      float mult = 0.25f/biggestVal; 

      // Apply table to compute quaternion values 
      switch (biggestIndex) { 
       case 0: 
        w = biggestVal; 
        x = (m23 - m32) * mult; 
        y = (m31 - m13) * mult; 
        z = (m12 - m21) * mult; 
        break; 
       case 1: 
        x = biggestVal; 
        w = (m23 - m32) * mult; 
        y = (m12 + m21) * mult; 
        z = (m31 + m13) * mult; 
        break; 
       case 2: 
        y = biggestVal; 
        w = (m31 - m13) * mult; 
        x = (m12 + m21) * mult; 
        z = (m23 + m32) * mult; 
        break; 
       case 3: 
        z = biggestVal; 
        w = (m12 - m21) * mult; 
        x = (m31 + m13) * mult; 
        y = (m23 + m32) * mult; 
        break; 

        quatX = x; 
        quatY = y; 
        quatZ = z; 
        quatW = w; 

        model = vec4(quatX,quatY,quatZ,quatW); 
       } 
      } 
+0

好吧,你在哪里初始化M11? –

+0

你的输入矩阵应该来自哪里? –

+0

这些值可以是随机的,这并不重要。我不确定矩阵中应该有什么值。 – user1283674

回答

0

让您的输入输入你的函数和点不留他们不确定:

void matrixIntoQuaternions(
      float m11, float m12, float m13, // Make these function parameters! 
      float m21, float m22, float m23, 
      float m31, float m32, float m33 
) 
{ 
    // Rest of your code... 
}