public Color GetRadiance(ShadingState state)
{
Point3[] p = new Point3[3];
if (!state.getTrianglePoints(p))
return getFillColor(state);
// transform points into camera space
Point3 center = state.getPoint();
Matrix4 w2c = state.getWorldToCamera();
center = w2c.transformP(center);
for (int i = 0; i < 3; i++)
p[i] = w2c.transformP(state.transformObjectToWorld(p[i]));
float cn = 1.0f / (float)Math.Sqrt(center.x * center.x + center.y * center.y + center.z * center.z);
for (int i = 0, i2 = 2; i < 3; i2 = i, i++)
{
// compute orthogonal projection of the shading point onto each
// triangle edge as in:
// http://mathworld.wolfram.com/Point-LineDistance3-Dimensional.html
float t = (center.x - p[i].x) * (p[i2].x - p[i].x);
t += (center.y - p[i].y) * (p[i2].y - p[i].y);
t += (center.z - p[i].z) * (p[i2].z - p[i].z);
t /= p[i].distanceToSquared(p[i2]);
float projx = (1 - t) * p[i].x + t * p[i2].x;
float projy = (1 - t) * p[i].y + t * p[i2].y;
float projz = (1 - t) * p[i].z + t * p[i2].z;
float n = 1.0f / (float)Math.Sqrt(projx * projx + projy * projy + projz * projz);
// check angular width
float dot = projx * center.x + projy * center.y + projz * center.z;
if (dot * n * cn >= cosWidth)
return getLineColor(state);
}
return getFillColor(state);
}
public Color GetRadiance(ShadingState state)
{
Point3[] p = new Point3[3];
if (!state.getTrianglePoints(p))
{
return(getFillColor(state));
}
// transform points into camera space
Point3 center = state.getPoint();
Matrix4 w2c = state.getWorldToCamera();
center = w2c.transformP(center);
for (int i = 0; i < 3; i++)
{
p[i] = w2c.transformP(state.transformObjectToWorld(p[i]));
}
float cn = 1.0f / (float)Math.Sqrt(center.x * center.x + center.y * center.y + center.z * center.z);
for (int i = 0, i2 = 2; i < 3; i2 = i, i++)
{
// compute orthogonal projection of the shading point onto each
// triangle edge as in:
// http://mathworld.wolfram.com/Point-LineDistance3-Dimensional.html
float t = (center.x - p[i].x) * (p[i2].x - p[i].x);
t += (center.y - p[i].y) * (p[i2].y - p[i].y);
t += (center.z - p[i].z) * (p[i2].z - p[i].z);
t /= p[i].distanceToSquared(p[i2]);
float projx = (1 - t) * p[i].x + t * p[i2].x;
float projy = (1 - t) * p[i].y + t * p[i2].y;
float projz = (1 - t) * p[i].z + t * p[i2].z;
float n = 1.0f / (float)Math.Sqrt(projx * projx + projy * projy + projz * projz);
// check angular width
float dot = projx * center.x + projy * center.y + projz * center.z;
if (dot * n * cn >= cosWidth)
{
return(getLineColor(state));
}
}
return(getFillColor(state));
}
public void prepareShadingState(ShadingState state)
{
state.init();
Instance parent = state.getInstance();
int primID = state.getPrimitiveID();
float u = state.getU();
float v = state.getV();
float w = 1 - u - v;
// state.getRay().getPoint(state.getPoint());
int tri = 3 * primID;
int index0 = triangleMesh.triangles[tri + 0];
int index1 = triangleMesh.triangles[tri + 1];
int index2 = triangleMesh.triangles[tri + 2];
Point3 v0p = triangleMesh.getPoint(index0);
Point3 v1p = triangleMesh.getPoint(index1);
Point3 v2p = triangleMesh.getPoint(index2);
// get object space point from barycentric coordinates
state.getPoint().x = w * v0p.x + u * v1p.x + v * v2p.x;
state.getPoint().y = w * v0p.y + u * v1p.y + v * v2p.y;
state.getPoint().z = w * v0p.z + u * v1p.z + v * v2p.z;
// move into world space
state.getPoint().set(state.transformObjectToWorld(state.getPoint()));
Vector3 ng = Point3.normal(v0p, v1p, v2p);
if (parent != null)
{
ng = state.transformNormalObjectToWorld(ng);
}
ng.normalize();
state.getGeoNormal().set(ng);
switch (triangleMesh.normals.interp)
{
case ParameterList.InterpolationType.NONE:
case ParameterList.InterpolationType.FACE:
{
state.getNormal().set(ng);
break;
}
case ParameterList.InterpolationType.VERTEX:
{
int i30 = 3 * index0;
int i31 = 3 * index1;
int i32 = 3 * index2;
float[] normals = triangleMesh.normals.data;
state.getNormal().x = w * normals[i30 + 0] + u * normals[i31 + 0] + v * normals[i32 + 0];
state.getNormal().y = w * normals[i30 + 1] + u * normals[i31 + 1] + v * normals[i32 + 1];
state.getNormal().z = w * normals[i30 + 2] + u * normals[i31 + 2] + v * normals[i32 + 2];
if (parent != null)
{
state.getNormal().set(state.transformNormalObjectToWorld(state.getNormal()));
}
state.getNormal().normalize();
break;
}
case ParameterList.InterpolationType.FACEVARYING:
{
int idx = 3 * tri;
float[] normals = triangleMesh.normals.data;
state.getNormal().x = w * normals[idx + 0] + u * normals[idx + 3] + v * normals[idx + 6];
state.getNormal().y = w * normals[idx + 1] + u * normals[idx + 4] + v * normals[idx + 7];
state.getNormal().z = w * normals[idx + 2] + u * normals[idx + 5] + v * normals[idx + 8];
if (parent != null)
{
state.getNormal().set(state.transformNormalObjectToWorld(state.getNormal()));
}
state.getNormal().normalize();
break;
}
}
float uv00 = 0, uv01 = 0, uv10 = 0, uv11 = 0, uv20 = 0, uv21 = 0;
switch (triangleMesh.uvs.interp)
{
case ParameterList.InterpolationType.NONE:
case ParameterList.InterpolationType.FACE:
{
state.getUV().x = 0;
state.getUV().y = 0;
break;
}
case ParameterList.InterpolationType.VERTEX:
{
int i20 = 2 * index0;
int i21 = 2 * index1;
int i22 = 2 * index2;
float[] uvs = triangleMesh.uvs.data;
uv00 = uvs[i20 + 0];
uv01 = uvs[i20 + 1];
uv10 = uvs[i21 + 0];
uv11 = uvs[i21 + 1];
uv20 = uvs[i22 + 0];
uv21 = uvs[i22 + 1];
break;
}
case ParameterList.InterpolationType.FACEVARYING:
{
int idx = tri << 1;
float[] uvs = triangleMesh.uvs.data;
uv00 = uvs[idx + 0];
uv01 = uvs[idx + 1];
uv10 = uvs[idx + 2];
uv11 = uvs[idx + 3];
uv20 = uvs[idx + 4];
uv21 = uvs[idx + 5];
break;
}
}
if (triangleMesh.uvs.interp != ParameterList.InterpolationType.NONE)
{
// get exact uv coords and compute tangent vectors
state.getUV().x = w * uv00 + u * uv10 + v * uv20;
state.getUV().y = w * uv01 + u * uv11 + v * uv21;
float du1 = uv00 - uv20;
float du2 = uv10 - uv20;
float dv1 = uv01 - uv21;
float dv2 = uv11 - uv21;
Vector3 dp1 = Point3.sub(v0p, v2p, new Vector3()), dp2 = Point3.sub(v1p, v2p, new Vector3());
float determinant = du1 * dv2 - dv1 * du2;
if (determinant == 0.0f)
{
// create basis in world space
state.setBasis(OrthoNormalBasis.makeFromW(state.getNormal()));
}
else
{
float invdet = 1 / determinant;
// Vector3 dpdu = new Vector3();
// dpdu.x = (dv2 * dp1.x - dv1 * dp2.x) * invdet;
// dpdu.y = (dv2 * dp1.y - dv1 * dp2.y) * invdet;
// dpdu.z = (dv2 * dp1.z - dv1 * dp2.z) * invdet;
Vector3 dpdv = new Vector3();
dpdv.x = (-du2 * dp1.x + du1 * dp2.x) * invdet;
dpdv.y = (-du2 * dp1.y + du1 * dp2.y) * invdet;
dpdv.z = (-du2 * dp1.z + du1 * dp2.z) * invdet;
if (parent != null)
{
dpdv = state.transformVectorObjectToWorld(dpdv);
}
// create basis in world space
state.setBasis(OrthoNormalBasis.makeFromWV(state.getNormal(), dpdv));
}
}
else
{
state.setBasis(OrthoNormalBasis.makeFromW(state.getNormal()));
}
int shaderIndex = triangleMesh.faceShaders == null ? 0 : (triangleMesh.faceShaders[primID] & 0xFF);
state.setShader(parent.getShader(shaderIndex));
}
