float4x4 ComputeCameraProjection()
{
float t = (float) (DateTime.Now - m_startTime).TotalSeconds;
// Make a camera orbiting around the cube
float T = t;
float3 cameraPosition = 3.0f * new float3( (float) Math.Cos( T ), (float) Math.Cos( 3 * T ), (float) Math.Sin( T ) );
float3 cameraTarget = new float3( 0, 0, 0 );
float4x4 camera2World = new float4x4();
camera2World.BuildRotLeftHanded( cameraPosition, cameraTarget, float3.UnitY );
// Build the perspective projection matrix
float4x4 camera2Proj = new float4x4();
camera2Proj.BuildProjectionPerspective( 80.0f * (float) Math.PI / 180.0f, (float) Width / Height, 0.01f, 100.0f );
// Compose the 2 matrices together to obtain the final matrix that transforms world coordinates into projected 2D coordinates
return camera2World.Inverse * camera2Proj;
}
static void TestFloat4x4()
{
if ( System.Runtime.InteropServices.Marshal.SizeOf(typeof(float4x4)) != 64 )
throw new Exception( "Not the appropriate size!" );
float4x4 test1 = new float4x4( new float[16] { 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1 } );
float4x4 test2 = new float4x4( new float4( 1, 0, 0, 0 ), new float4( 0, 1, 0, 0 ), new float4( 0, 0, 1, 0 ), new float4( 0, 0, 0, 1 ) );
float4x4 test3 = new float4x4( 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 );
float4x4 test0;
test0 = test3;
test2.Scale( new float3( 2, 2, 2 ) );
float3x3 cast = (float3x3) test3;
float4x4 mul0 = test1 * test2;
float4x4 mul1 = 3.0f * test2;
float4 mul2 = new float4( 1, 1, 1, 1 ) * test3;
float4 access0 = test3[2];
test3[1] = new float4( 12, 13, 14, 15 );
float access1 = test3[1,2];
test3[1,2] = 18;
float coFactor = test3.CoFactor( 0, 2 );
float det = test3.Determinant;
float4x4 inv = test2.Inverse;
float4x4 id = float4x4.Identity;
test3.BuildRotLeftHanded( float3.UnitZ, float3.Zero, float3.UnitY );
test3.BuildRotRightHanded( float3.UnitZ, float3.Zero, float3.UnitY );
test3.BuildProjectionPerspective( 1.2f, 2.0f, 0.01f, 10.0f );
test3.BuildRotationX( 0.5f );
test3.BuildRotationY( 0.5f );
test3.BuildRotationZ( 0.5f );
test3.BuildFromAngleAxis( 0.5f, float3.UnitY );
}
/// <summary>
/// Makes the camera look at the specified target from the specified eye position
/// </summary>
/// <param name="_Eye"></param>
/// <param name="_Target"></param>
/// <param name="_Up"></param>
public void LookAt( float3 _Eye, float3 _Target, float3 _Up )
{
float4x4 Temp = new float4x4();
Temp.BuildRotLeftHanded( _Eye, _Target, _Up );
this.Camera2World = Temp;
}
