public Camera(SceneGraph graph, Vec3 position, Vec3 target, Vec3 upDirection, ViewingFrustum frustum,
float aspectRatio) : base(graph)
{
Position = position;
Target = target;
UpDirection = upDirection;
Frustum = frustum;
}
public Mat4[] CameraToCsmProjections(Camera camera, int count)
{
var camToLight = Mat.LookAt(-DirectionInCameraSpace(camera), new Vec3(0f, 1f, 0f));
return((from frustum in camera.SplitFrustumsForCascadedShadowMaps(count, 0.75f)
let corners = frustum.Corners.Map(p => camToLight.Transform(p))
let orthoBox = ViewingFrustum.FromBBox(Aabb <Vec3> .FromPositions(corners))
select orthoBox.CameraToScreen *camToLight)
.ToArray());
}
public Mat4 CameraToShadowProjection(Camera camera)
{
var extent = MaxShadowDepth * 0.5f;
var lightLookAt = -DirectionInCameraSpace(camera);
var camToLight = Mat.Translation <Mat4> (0f, 0f, -extent)
* Mat.LookAt(lightLookAt, new Vec3(0f, 1f, 0f))
* Mat.Translation <Mat4> (0f, 0f, extent);
var shadowFrustum = new ViewingFrustum(FrustumKind.Orthographic, MaxShadowDepth, MaxShadowDepth,
0f, -MaxShadowDepth);
return(shadowFrustum.CameraToScreen * camToLight);
}
private ViewingFrustum[] CreateSplitFrustums(int splitCount, float logarithmicWeight)
{
var splits = CSMFrustumSplit(splitCount, logarithmicWeight);
var result = new ViewingFrustum[splitCount];
for (int i = 0; i < splitCount; i++)
{
var nearPlane = _frustum.XYPlaneAtZ(splits[i]);
result[i] = new ViewingFrustum(_frustum.Kind, nearPlane.X, nearPlane.Z, nearPlane.Y,
nearPlane.W, splits[i], splits[i + 1]);
}
return(result);
}