protected static void viewProjFromLightAlignedBB(ref SSAABB bb,
ref Matrix4 lightTransform,
ref Vector3 lightY,
out Matrix4 viewMatrix,
out Matrix4 projMatrix)
{
// Use center of AABB in regular coordinates to get the view matrix
Vector3 targetLightSpace = bb.Center();
Vector3 eyeLightSpace = new Vector3(targetLightSpace.X,
targetLightSpace.Y,
bb.Min.Z);
Vector3 viewTarget = Vector3.Transform(targetLightSpace, lightTransform.Inverted());
Vector3 viewEye = Vector3.Transform(eyeLightSpace, lightTransform.Inverted());
Vector3 viewUp = lightY;
viewMatrix = Matrix4.LookAt(viewEye, viewTarget, viewUp);
// Finish the projection matrix
Vector3 diff = bb.Diff();
float width, height, nearZ, farZ;
width = diff.X;
height = diff.Y;
nearZ = 1f;
farZ = 1f + diff.Z;
projMatrix = Matrix4.CreateOrthographic(width, height, nearZ, farZ);
}
/// <summary>
/// Computes vertex positions and normals (based on the state of runtime joint hierarchy).
/// Updates VBO with the result.
/// </summary>
/// <returns>AABB of the vertices.</returns>
public SSAABB ComputeVertices()
{
SSAABB aabb = new SSAABB(float.PositiveInfinity, float.NegativeInfinity);
for (int v = 0; v < m_runtimeMesh.numVertices; ++v)
{
// position
Vector3 pos = m_runtimeMesh.computeVertexPos(v);
m_vertices [v].Position = pos;
aabb.UpdateMin(pos);
aabb.UpdateMax(pos);
// normal
m_vertices [v].Normal = m_runtimeMesh.computeVertexNormal(v);
}
vbo.UpdateBufferData(m_vertices);
return(aabb);
}
// Ray to AABB (AxisAlignedBoundingBox)
// http://gamedev.stackexchange.com/questions/18436/most-efficient-aabb-vs-ray-collision-algorithms
public static bool intersectRayAABox2(SSRay ray, SSAABB box, ref float tnear, ref float tfar)
{
Vector3d T_1 = new Vector3d();
Vector3d T_2 = new Vector3d(); // vectors to hold the T-values for every direction
double t_near = double.MinValue; // maximums defined in float.h
double t_far = double.MaxValue;
for (int i = 0; i < 3; i++) //we test slabs in every direction
{
if (ray.dir[i] == 0) // ray parallel to planes in this direction
{
if ((ray.pos[i] < box.Min[i]) || (ray.pos[i] > box.Max[i]))
{
return(false); // parallel AND outside box : no intersection possible
}
}
else // ray not parallel to planes in this direction
{
T_1[i] = (box.Min[i] - ray.pos[i]) / ray.dir[i];
T_2[i] = (box.Max[i] - ray.pos[i]) / ray.dir[i];
if (T_1[i] > T_2[i]) // we want T_1 to hold values for intersection with near plane
{
var swp = T_2; // swap
T_1 = swp; T_2 = T_1;
}
if (T_1[i] > t_near)
{
t_near = T_1[i];
}
if (T_2[i] < t_far)
{
t_far = T_2[i];
}
if ((t_near > t_far) || (t_far < 0))
{
return(false);
}
}
}
tnear = (float)t_near; tfar = (float)t_far; // put return values in place
return(true); // if we made it here, there was an intersection - YAY
}
public override void renderMesh(SSRenderConfig renderConfig)
{
// apply animation channels
_hierarchy.applySkeletalControllers(_channelControllers);
SSAABB totalAABB = new SSAABB(float.PositiveInfinity, float.NegativeInfinity);
foreach (var sub in _renderSubMeshes)
{
SSAABB aabb = sub.ComputeVertices();
sub.renderMesh(renderConfig);
totalAABB.ExpandBy(aabb);
}
// update the bounding sphere
var sphere = totalAABB.ToSphere();
base.boundingSphereCenter = sphere.center;
base.boundingSphereRadius = sphere.radius;
NotifyMeshPositionOrSizeChanged();
}
} // fn
public static bool intersectRayAABox1(SSRay ray, SSAABB box, ref float tnear, ref float tfar)
{
// r.dir is unit direction vector of ray
Vector3 dirfrac = new Vector3();
float t;
dirfrac.X = 1.0f / ray.dir.X;
dirfrac.Y = 1.0f / ray.dir.Y;
dirfrac.Z = 1.0f / ray.dir.Z;
// lb is the corner of AABB with minimal coordinates - left bottom, rt is maximal corner
// r.org is origin of ray
float t1 = (box.Min.X - ray.pos.X) * dirfrac.X;
float t2 = (box.Max.X - ray.pos.X) * dirfrac.X;
float t3 = (box.Min.Y - ray.pos.Y) * dirfrac.Y;
float t4 = (box.Max.Y - ray.pos.Y) * dirfrac.Y;
float t5 = (box.Min.Z - ray.pos.Z) * dirfrac.Z;
float t6 = (box.Max.Z - ray.pos.Z) * dirfrac.Z;
float tmin = Math.Max(Math.Max(Math.Min(t1, t2), Math.Min(t3, t4)), Math.Min(t5, t6));
float tmax = Math.Min(Math.Min(Math.Max(t1, t2), Math.Max(t3, t4)), Math.Max(t5, t6));
// if tmax < 0, ray (line) is intersecting AABB, but whole AABB is behing us
if (tmax < 0)
{
t = tmax;
return(false);
}
// if tmin > tmax, ray doesn't intersect AABB
if (tmin > tmax)
{
t = tmax;
return(false);
}
t = tmin;
return(true);
}
public bool IntersectsAABB(SSAABB aabb)
{
return(aabb.IntersectsSphere(this));
}
protected void ComputeProjections(
List <SSObject> objects,
Matrix4 cameraView,
Matrix4 cameraProj,
float fov, float aspect, float cameraNearZ, float cameraFarZ)
{
if (m_light.GetType() != typeof(SSDirectionalLight))
{
throw new NotSupportedException();
}
SSDirectionalLight dirLight = (SSDirectionalLight)m_light;
// light-aligned unit vectors
Vector3 lightZ = dirLight.Direction.Normalized();
Vector3 lightX, lightY;
OpenTKHelper.TwoPerpAxes(lightZ, out lightX, out lightY);
// transform matrix from regular space into light aligned space
Matrix4 lightTransform = new Matrix4(
lightX.X, lightX.Y, lightX.Z, 0f,
lightY.X, lightY.Y, lightY.Z, 0f,
lightZ.X, lightZ.Y, lightZ.Z, 0f,
0f, 0f, 0f, 0f
);
// Step 0: camera projection matrix (nearZ and farZ modified) for each frustum split
float prevFarZ = cameraNearZ;
for (int i = 0; i < c_numberOfSplits; ++i)
{
// generate frustum splits using Practical Split Scheme (GPU Gems 3, 10.2.1)
float iRatio = (float)(i + 1) / (float)c_numberOfSplits;
float cLog = cameraNearZ * (float)Math.Pow(cameraFarZ / cameraNearZ, iRatio);
float cUni = cameraNearZ + (cameraFarZ - cameraNearZ) * iRatio;
float nextFarZ = LogVsLinearSplitFactor * cLog + (1f - LogVsLinearSplitFactor) * cUni;
float nextNearZ = prevFarZ;
// exported to the shader
m_viewSplits [i] = nextFarZ;
// create a view proj matrix with the nearZ, farZ values for the current split
m_frustumViewProjMatrices[i] = cameraView
* Matrix4.CreatePerspectiveFieldOfView(fov, aspect, nextNearZ, nextFarZ);
// create light-aligned AABBs of frustums
m_frustumLightBB [i] = SSAABB.FromFrustum(ref lightTransform, ref m_frustumViewProjMatrices [i]);
prevFarZ = nextFarZ;
}
#if true
// Optional scene-dependent optimization
for (int i = 0; i < c_numberOfSplits; ++i)
{
m_objsLightBB[i] = new SSAABB(float.PositiveInfinity, float.NegativeInfinity);
m_splitFrustums[i] = new SSFrustumCuller(ref m_frustumViewProjMatrices[i]);
m_shrink[i] = false;
}
foreach (var obj in objects)
{
// pass through all shadow casters and receivers
if (obj.renderState.toBeDeleted || obj.localBoundingSphereRadius <= 0f ||
!obj.renderState.visible || !obj.renderState.receivesShadows)
{
continue;
}
else
{
for (int i = 0; i < c_numberOfSplits; ++i)
{
if (m_splitFrustums[i].isSphereInsideFrustum(obj.worldBoundingSphere))
{
// determine AABB in light coordinates of the objects so far
m_shrink[i] = true;
Vector3 lightAlignedPos = Vector3.Transform(obj.worldBoundingSphereCenter, lightTransform);
Vector3 rad = new Vector3(obj.worldBoundingSphereRadius);
Vector3 localMin = lightAlignedPos - rad;
Vector3 localMax = lightAlignedPos + rad;
m_objsLightBB[i].UpdateMin(localMin);
m_objsLightBB[i].UpdateMax(localMax);
}
}
}
}
#endif
for (int i = 0; i < c_numberOfSplits; ++i)
{
if (m_shrink [i])
{
m_resultLightBB[i].Min = Vector3.ComponentMax(m_frustumLightBB [i].Min,
m_objsLightBB [i].Min);
m_resultLightBB [i].Max = Vector3.ComponentMin(m_frustumLightBB [i].Max,
m_objsLightBB [i].Max);
}
else
{
m_resultLightBB [i] = m_frustumLightBB [i];
}
}
for (int i = 0; i < c_numberOfSplits; ++i)
{
// Obtain view + projection + crop matrix, need it later
Matrix4 shadowView, shadowProj;
viewProjFromLightAlignedBB(ref m_resultLightBB [i], ref lightTransform, ref lightY,
out shadowView, out shadowProj);
m_shadowViewProjMatrices[i] = shadowView * shadowProj * c_cropMatrices[i];
// obtain view + projection + clio + bias
m_shadowViewProjBiasMatrices[i] = m_shadowViewProjMatrices[i] * c_biasMatrix;
// There is, currently, no mathematically derived solution to how much Poisson spread scaling
// you need for each split. Current improvisation combines 1) increasing spread for the near
// splits; reducing spread for the far splits and 2) reducing spread for splits with larger
// light-aligned areas; increasing spread for splits with smaller light-aligned areas
m_poissonScaling [i] = m_resultLightBB [i].Diff().Xy / (100f * (float)Math.Pow(3.0, i - 1));
}
// Combine all splits' BB into one and extend it to include shadow casters closer to light
SSAABB castersLightBB = new SSAABB(float.PositiveInfinity, float.NegativeInfinity);
for (int i = 0; i < c_numberOfSplits; ++i)
{
castersLightBB.Combine(ref m_resultLightBB [i]);
}
// extend Z of the AABB to cover shadow-casters closer to the light
foreach (var obj in objects)
{
if (obj.renderState.toBeDeleted || obj.localBoundingSphereRadius <= 0f ||
!obj.renderState.visible || !obj.renderState.castsShadow)
{
continue;
}
else
{
Vector3 lightAlignedPos = Vector3.Transform(obj.worldBoundingSphereCenter, lightTransform);
Vector3 rad = new Vector3(obj.worldBoundingSphereRadius);
Vector3 localMin = lightAlignedPos - rad;
Vector3 localMax = lightAlignedPos + rad;
if (localMin.Z < castersLightBB.Min.Z)
{
if (OpenTKHelper.RectsOverlap(castersLightBB.Min.Xy,
castersLightBB.Max.Xy,
localMin.Xy,
localMax.Xy))
{
castersLightBB.Min.Z = localMin.Z;
}
}
}
}
// Generate frustum culler from the BB extended towards light to include shadow casters
Matrix4 frustumView, frustumProj;
viewProjFromLightAlignedBB(ref castersLightBB, ref lightTransform, ref lightY,
out frustumView, out frustumProj);
Matrix4 frustumMatrix = frustumView * frustumProj;
FrustumCuller = new SSFrustumCuller(ref frustumMatrix);
}
private void ComputeProjections(List <SSObject> objects,
SSLightBase light,
Matrix4 cameraView, Matrix4 cameraProj)
{
if (light.GetType() != typeof(SSDirectionalLight))
{
throw new NotSupportedException();
}
SSDirectionalLight dirLight = (SSDirectionalLight)light;
// light-aligned unit vectors
Vector3 lightZ = dirLight.Direction.Normalized();
Vector3 lightX, lightY;
OpenTKHelper.TwoPerpAxes(lightZ, out lightX, out lightY);
// transform matrix from regular space into light aligned space
Matrix4 lightTransform = new Matrix4(
lightX.X, lightX.Y, lightX.Z, 0f,
lightY.X, lightY.Y, lightY.Z, 0f,
lightZ.X, lightZ.Y, lightZ.Z, 0f,
0f, 0f, 0f, 0f
);
// Find AABB of frustum corners in light coordinates
Matrix4 cameraViewProj = cameraView * cameraProj;
SSAABB frustumLightBB = SSAABB.FromFrustum(ref lightTransform, ref cameraViewProj);
bool shrink = false;
SSAABB objsLightBB = new SSAABB(float.PositiveInfinity, float.NegativeInfinity);
#if true
// (optional) scene dependent optimization
// Trim the light-bounding box by the shadow receivers (only in light-space x,y,maxz)
SSFrustumCuller cameraFrustum = new SSFrustumCuller(ref cameraViewProj);
foreach (var obj in objects)
{
// pass through all shadow casters and receivers
if (obj.renderState.toBeDeleted || !obj.renderState.visible ||
!obj.renderState.receivesShadows || obj.localBoundingSphereRadius <= 0f)
{
continue;
}
else if (cameraFrustum.isSphereInsideFrustum(obj.worldBoundingSphere))
{
// determine AABB in light coordinates of the objects so far
shrink = true;
Vector3 lightAlignedPos = Vector3.Transform(obj.worldBoundingSphereCenter, lightTransform);
Vector3 rad = new Vector3(obj.worldBoundingSphereRadius);
Vector3 localMin = lightAlignedPos - rad;
Vector3 localMax = lightAlignedPos + rad;
objsLightBB.UpdateMin(localMin);
objsLightBB.UpdateMax(localMax);
}
}
#endif
// Optimize the light-frustum-projection bounding box by the object-bounding-box
SSAABB resultLightBB = new SSAABB(float.PositiveInfinity, float.NegativeInfinity);
if (shrink)
{
// shrink the XY & far-Z coordinates..
resultLightBB.Min.Xy = Vector2.ComponentMax(frustumLightBB.Min.Xy, objsLightBB.Min.Xy);
resultLightBB.Min.Z = objsLightBB.Min.Z;
resultLightBB.Max = Vector3.ComponentMin(frustumLightBB.Max, objsLightBB.Max);
}
else
{
resultLightBB = frustumLightBB;
}
// View and projection matrices, used by the scene later
viewProjFromLightAlignedBB(ref resultLightBB, ref lightTransform, ref lightY,
out m_shadowViewMatrix, out m_shadowProjMatrix);
// Now extend Z of the result AABB to cover shadow-casters closer to the light inside the
// original box
foreach (var obj in objects)
{
if (obj.renderState.toBeDeleted || !obj.renderState.visible ||
!obj.renderState.castsShadow || obj.localBoundingSphereRadius <= 0f)
{
continue;
}
Vector3 lightAlignedPos = Vector3.Transform(obj.worldBoundingSphereCenter, lightTransform);
Vector3 rad = new Vector3(obj.worldBoundingSphereRadius);
Vector3 localMin = lightAlignedPos - rad;
if (localMin.Z < resultLightBB.Min.Z)
{
Vector3 localMax = lightAlignedPos + rad;
if (OpenTKHelper.RectsOverlap(resultLightBB.Min.Xy,
resultLightBB.Max.Xy,
localMin.Xy,
localMax.Xy))
{
resultLightBB.Min.Z = localMin.Z;
}
}
}
// Generate frustum culler from the BB extended towards light to include shadow casters
Matrix4 frustumView, frustumProj;
viewProjFromLightAlignedBB(ref resultLightBB, ref lightTransform, ref lightY,
out frustumView, out frustumProj);
Matrix4 frustumMatrix = frustumView * frustumProj;
FrustumCuller = new SSFrustumCuller(ref frustumMatrix);
}
private SSSkeletalAnimationMD5 readAnimation()
{
Match[] matches;
// header
seekEntry("MD5Version", "10");
seekEntry("commandline", SSMD5Parser._quotedStrRegex);
matches = seekEntry("numFrames", SSMD5Parser._uintRegex);
var numFrames = Convert.ToInt32(matches [1].Value);
matches = seekEntry("numJoints", SSMD5Parser._uintRegex);
var numJoints = Convert.ToInt32(matches [1].Value);
matches = seekEntry("frameRate", SSMD5Parser._uintRegex);
var frameRate = Convert.ToInt32(matches [1].Value);
matches = seekEntry("numAnimatedComponents", SSMD5Parser._uintRegex);
int numAnimatedComponents = Convert.ToInt32(matches [1].Value);
var floatComponents = new float[numAnimatedComponents];
// hierarchy
seekEntry("hierarchy", "{");
var hierarchy = new SSSkeletalJoint[numJoints];
var flags = new byte[numJoints];
for (int j = 0; j < numJoints; ++j)
{
hierarchy [j] = readHierarchyEntry(out flags [j]);
}
seekEntry("}");
// bounds
seekEntry("bounds", "{");
var bounds = new SSAABB[numFrames];
for (int f = 0; f < numFrames; ++f)
{
bounds [f] = readBounds();
}
seekEntry("}");
// base frame
seekEntry("baseframe", "{");
for (int j = 0; j < numJoints; ++j)
{
hierarchy[j].bindPoseLocation = readBaseFrame();
}
seekEntry("}");
// frames
var frames = new SSSkeletalJointLocation[numFrames][];
for (int f = 0; f < numFrames; ++f)
{
matches = seekEntry("frame", SSMD5Parser._uintRegex, "{");
int frameIdx = Convert.ToInt32(matches [1].Value);
frames [frameIdx] = readFrameJoints(flags, hierarchy, floatComponents);
seekEntry("}");
}
return(new SSSkeletalAnimationMD5(frameRate, hierarchy, frames, bounds));
}
