private void Render(GeometryModel3D model)
{
if (model.Geometry is MeshGeometry3D)
{
// Project geometry into a list of triangles
ProjectedGeometry pg = MeshToProjectedGeometry((MeshGeometry3D)model.Geometry, model.Transform);
// Remember the view matrix for view space lighting
Matrix3D view = MatrixUtils.ViewMatrix(camera);
// Render back faces
RenderGeometry(pg, view, model.BackMaterial, VisibleFaces.Back);
// Render front faces
RenderGeometry(pg, view, model.Material, VisibleFaces.Front);
}
else if (model.Geometry == null)
{
// do nothing
}
else
{
throw new NotSupportedException("I cannot render Geometry3D of type: " + model.Geometry.GetType());
}
}
private void Render(ScreenSpaceLines3D lines)
{
ProjectedGeometry geometry = MagicLinesToProjectedGeometry(lines, lines.Transform);
Shader shader = new ScreenSpaceLinesShader(geometry.FrontFaceTriangles, buffer);
shader.Rasterize(bounds.RenderBounds);
// SSL are always front facing ( CCW winding ) triangles
RenderSilhouetteTolerance(geometry, buffer, VisibleFaces.Front);
}
private void RenderGeometry(ProjectedGeometry pg, Matrix3D view, Material material, VisibleFaces faces)
{
if (material == null)
{
return;
}
Triangle[] triangles = null;
// Choose list based on triangle winding/facing
switch (faces)
{
case VisibleFaces.Front:
triangles = pg.FrontFaceTriangles;
break;
case VisibleFaces.Back:
triangles = pg.BackFaceTriangles;
break;
default:
throw new NotSupportedException("Cannot render these type of faces: " + faces.ToString());
}
// We should only look into materials if we have any geometry to render.
// Doing otherwise will throw exceptions when trying to use screen-space
// bounds or UV coordinates.
if (triangles.Length > 0)
{
// Create a flat, ordered list of textures to apply to this model
List <Material> materials = ExtractMaterials(material);
// Create a list of textures from the materials
TextureFilter[] textures = TextureFilter.CreateTextures(
materials, pg.OriginalMinUV, pg.OriginalMaxUV, Rect.Intersect(bounds.RenderBounds, pg.ScreenSpaceBounds));
// Use a precomputed light shader
Shader shader = null;
if (interpolation == InterpolationMode.Phong)
{
shader = new PrecomputedPhongShader(triangles, buffer, lights, textures, view);
}
else
{
shader = new PrecomputedGouraudShader(triangles, buffer, lights, textures, view);
}
shader.Rasterize(bounds.RenderBounds);
RenderSilhouetteTolerance(pg, buffer, faces);
}
}
private void RenderSilhouetteTolerance(ProjectedGeometry geometry, RenderBuffer rasterization, VisibleFaces faces)
{
List <Edge> silhouetteEdges = null;
// Choose list based on triangle winding/facing
switch (faces)
{
case VisibleFaces.Front:
silhouetteEdges = geometry.FrontFaceSilhouetteEdges;
break;
case VisibleFaces.Back:
silhouetteEdges = geometry.BackFaceSilhouetteEdges;
break;
default:
throw new NotSupportedException("Cannot render these type of faces: " + faces);
}
// Outline edge detection
if (RenderTolerance.SilhouetteEdgeTolerance > 0)
{
// Create a set of triangles that will draw lines on the tolerance buffer
SilhouetteEdgeTriangle[] edgeTriangles = new SilhouetteEdgeTriangle[2 * silhouetteEdges.Count];
int count = 0;
//double the silhouette pixel tolerance in nonstandard DPI scenario.
//This compensates for differences in anti-aliasing sampling patterns in high and low DPI
double tolerance = RenderTolerance.SilhouetteEdgeTolerance;
if (!RenderTolerance.IsSquare96Dpi)
{
tolerance *= 4;
}
foreach (Edge edge in silhouetteEdges)
{
// FWD triangle
edgeTriangles[count++] = new SilhouetteEdgeTriangle(edge.Start, edge.End, tolerance);
// BWD triangle
edgeTriangles[count++] = new SilhouetteEdgeTriangle(edge.End, edge.Start, tolerance);
}
// Render our ignore geometry onto the tolerance buffer.
RenderToToleranceShader edgeIgnore = new RenderToToleranceShader(edgeTriangles, rasterization);
edgeIgnore.Rasterize(bounds.RenderBounds);
}
}
internal MeshGeometry3D ExtractTrianglesAtPoints(
MeshGeometry3D mesh,
Transform3D tx,
Point[] selectionPoints)
{
ProjectedGeometry pg = MeshToProjectedGeometry(mesh, tx);
MeshGeometry3D outputMesh = new MeshGeometry3D();
foreach (Triangle t in pg.FrontFaceTriangles)
{
foreach (Point p in selectionPoints)
{
if (t.Bounds.Contains(p.X + pixelCenterX, p.Y + pixelCenterY) &&
t.Contains(p.X + pixelCenterX, p.Y + pixelCenterY))
{
t.SaveToMesh(outputMesh);
// saving the triangle once is enough
break;
}
}
}
foreach (Triangle t in pg.BackFaceTriangles)
{
foreach (Point p in selectionPoints)
{
if (t.Bounds.Contains(p.X + pixelCenterX, p.Y + pixelCenterY) &&
t.Contains(p.X + pixelCenterX, p.Y + pixelCenterY))
{
// Back facing ... flip normals
t.vertex1.Normal *= -1;
t.vertex2.Normal *= -1;
t.vertex3.Normal *= -1;
t.SaveToMesh(outputMesh);
// saving the triangle once is enough
break;
}
}
}
return(outputMesh);
}