static SKMatrix44 GetMatrix(VoxelData voxelData, int size)
{
var r = 1.61803398875f;
var d = size / (r * voxelData.size.MaxDimension);
var tran = SKMatrix44.CreateTranslate(size * 0.5f, size * 0.5f, 0);
var rotx = SKMatrix44.CreateRotationDegrees(1, 0, 0, -26f);
var roty = SKMatrix44.CreateRotationDegrees(0, 1, 0, 45);
var matrix = SKMatrix44.CreateIdentity();
matrix.PreConcat(tran);
matrix.PreConcat(rotx);
matrix.PreConcat(roty);
matrix.PreScale(d, -d, d);
matrix.PreTranslate(-voxelData.size.X * 0.5f, -voxelData.size.Z * 0.5f, voxelData.size.Y * 0.5f);
return(matrix);
}
public void Matrix44MapsScalars()
{
// translate
var matrixTranslate = SKMatrix44.CreateTranslate(10, 20, 0);
var resultTranslateZero = matrixTranslate.MapScalars(0, 0, 0, 1);
var resultTranslateValue = matrixTranslate.MapScalars(5, 25, 0, 1);
Assert.Equal(new[] { 10f, 20f, 0f, 1f }, resultTranslateZero);
Assert.Equal(new[] { 15f, 45f, 0f, 1f }, resultTranslateValue);
// rotate
var matrixRotate = SKMatrix44.CreateRotationDegrees(0, 1, 0, 90);
var resultRotateZero = matrixRotate.MapScalars(0, 0, 0, 1);
var resultRotateValue = matrixRotate.MapScalars(5, 25, 0, 1);
Assert.Equal(new[] { 0f, 0f, 0f, 1f }, resultRotateZero);
Assert.Equal(new[] { 0f, 25f, -5f, 1f }, resultRotateValue.Select(v => (int)(v / EPSILON) * EPSILON));
}
public void Matrix44MapsPointsBulk()
{
var rnd = new Random();
var matrixTranslate = SKMatrix44.CreateTranslate(10, 25, 0);
// generate some points
var points = new SKPoint[1000];
var results = new SKPoint[points.Length];
for (int i = 0; i < points.Length; i++)
{
points[i] = new SKPoint(rnd.Next(1000) / 10f, rnd.Next(1000) / 10f);
results[i] = new SKPoint(points[i].X + 10, points[i].Y + 25);
}
var actualResults = matrixTranslate.MapPoints(points);
Assert.Equal(results, actualResults);
}
public void Matrix44MapsPoints()
{
// translate
var matrixTranslate = SKMatrix44.CreateTranslate(10, 20, 0);
var resultTranslateZero = matrixTranslate.MapPoint(SKPoint.Empty);
var resultTranslateValue = matrixTranslate.MapPoint(new SKPoint(5, 25));
Assert.Equal(new SKPoint(10f, 20f), resultTranslateZero);
Assert.Equal(new SKPoint(15f, 45f), resultTranslateValue);
// rotate
var matrixRotate = SKMatrix44.CreateRotationDegrees(0, 1, 0, 90);
var resultRotateZero = matrixRotate.MapPoint(SKPoint.Empty);
var resultRotateValue = matrixRotate.MapPoint(new SKPoint(5, 25));
Assert.Equal(new SKPoint(0f, 0f), resultRotateZero);
Assert.Equal(0, resultRotateValue.X, PRECISION);
Assert.Equal(25, resultRotateValue.Y, PRECISION);
}