矩阵投影

摄像机的矩阵

https://www.cnblogs.com/w-wfy/p/7243459.html

//关于矩阵我建议还是看一下上面这个网址 理解一下什么是unity里的矩阵

代码如下：

       static Matrix4x4 PerspectiveOffCenter(float left, float right, float bottom, float top, float near, float far)

       {

           float x = 2.0F * near / (right - left);

           float y = 2.0F * near / (top - bottom);

           float a = (right + left) / (right - left);

           float b = (top + bottom) / (top - bottom);

           float c = -(far + near) / (far - near);

           float d = -(2.0F * far * near) / (far - near);

           float e = -1.0F;

           Matrix4x4 m = new Matrix4x4();

           m[0, 0] = x;

           m[0, 1] = 0;

           m[0, 2] = a;

           m[0, 3] = 0;

           m[1, 0] = 0;

           m[1, 1] = y;

           m[1, 2] = b;

           m[1, 3] = 0;

           m[2, 0] = 0;

           m[2, 1] = 0;

           m[2, 2] = c;

           m[2, 3] = d;

           m[3, 0] = 0;

           m[3, 1] = 0;

           m[3, 2] = e;

           m[3, 3] = 0;

           return m;

       }

void UpdateLeftRightEyeCameraAndProjMatrix()

       {

           //更新投影矩阵

           //左眼

           float Cam_y = Left_Cam.transform.position.y;

           float left = (-x_left - Len_Rect / 2) / Cam_y * Left_Cam.nearClipPlane;

           float right = (-x_left + Len_Rect / 2) / Cam_y * Left_Cam.nearClipPlane;

           float top = (-z_left + Len_Rect / 2) / Cam_y * Left_Cam.nearClipPlane;

           float bottom = (-z_left - Len_Rect / 2) / Cam_y * Left_Cam.nearClipPlane;

           Matrix4x4 m = PerspectiveOffCenter(left, right, bottom, top, Left_Cam.nearClipPlane, Left_Cam.farClipPlane);

           Left_Cam.projectionMatrix = m;

           //主摄像机 右眼

           Cam_y = Right_Cam.transform.position.y;

           left = (-x_right - Len_Rect / 2) / Cam_y * Right_Cam.nearClipPlane;

           right = (-x_right + Len_Rect / 2) / Cam_y * Right_Cam.nearClipPlane;

           top = (-z_right + Len_Rect / 2) / Cam_y * Right_Cam.nearClipPlane;

           bottom = (-z_right - Len_Rect / 2) / Cam_y * Right_Cam.nearClipPlane;

           m = PerspectiveOffCenter(left, right, bottom, top, Right_Cam.nearClipPlane, Right_Cam.farClipPlane);

           Right_Cam.projectionMatrix = m;

       }

说一下  以左眼为例子

//左眼

           float Cam_y = Left_Cam.transform.position.y;

           float left = (-x_left - Len_Rect / 2) / Cam_y * Left_Cam.nearClipPlane;

           float right = (-x_left + Len_Rect / 2) / Cam_y * Left_Cam.nearClipPlane;

           float top = (-z_left + Len_Rect / 2) / Cam_y * Left_Cam.nearClipPlane;

           float bottom = (-z_left - Len_Rect / 2) / Cam_y * Left_Cam.nearClipPlane;

Matrix4x4 m = PerspectiveOffCenter(left, right, bottom, top, Left_Cam.nearClipPlane, Left_Cam.farClipPlane);

           Left_Cam.projectionMatrix = m;

-x_Left是我左眼的坐标的x值,Len_Rect是我矩阵投影的边长，计算完再乘一个比例就是我近切面的左边坐标，right top bottom 相同，关系如下图：求float left

这样两个摄像头的矩阵投影是重合的