// returns instance index or -1 if instance not found
private int GetHitInstanceIndex(RayMeshGeometry3DHitTestResult rayHitResult)
{
var modelHit = rayHitResult.ModelHit;
// When WPF GeometryModel3D objects are crated with InstancedMeshGeometryVisual3D,
// each GeometryModel3D has a InstancedMeshGeometryVisual3D.InstanceIndexProperty set to an int value
// that represent an index of the instance.
int hitInstanceIndex = (int)modelHit.GetValue(InstancedMeshGeometryVisual3D.InstanceIndexProperty);
if (hitInstanceIndex == -1) // If InstanceIndexProperty was not set, then we get a default value of -1.
{
// In this case we need to use the slower path
// of finding the instance index from the bounds of the hit Model3D.
// InstanceData.GetHitInstanceIndex method gets the instance index in the _instancedData array that has the bounds set to hitBounds
// The last parameter (useOnlyMatrixTranslation) can be set to true when the InstanceData define only translation (OffsetX, OffsetY, OffsetZ) and no scale or rotation.
// In this case a faster code path can be taken. When useOnlyMatrixTranslation is false (by default) a full matrix transformation is executed on each position.
Rect3D hitBounds = rayHitResult.ModelHit.Bounds;
hitInstanceIndex = InstanceData.GetHitInstanceIndex(hitBounds, _instanceMeshGeometry3D.Bounds, _instancedData, useOnlyMatrixTranslation: false);
// If not found then hitInstanceIndex is -1
}
return(hitInstanceIndex);
}
private InstancedMeshGeometryVisual3D AddInstancedTubePath(Point3DCollection spiralPositionCollection, Color4 tubeColor)
{
// Setup InstanceData
var instanceData = new InstanceData[spiralPositionCollection.Count];
// Convert to list of Vector3
var dxCurvePositions = spiralPositionCollection.Select(p => p.ToVector3()).ToList();
// NOTE:
// When a tube path is created from a lot of positions,
// then it is worth to transform the following loop into Parallel.For loop.
var startPosition = dxCurvePositions[0];
for (int i = 1; i < dxCurvePositions.Count; i++)
{
var endPosition = dxCurvePositions[i];
var direction = endPosition - startPosition;
var length = direction.Length(); // length will be used for x scale
var scale = new Vector3(length, 1, 1);
//direction.Normalize(); // Because we already have length, we can quickly normalize with simply dividing by length
direction /= length;
instanceData[i].World = Common.MatrixUtils.GetMatrixFromNormalizedDirection(direction, startPosition, scale);
instanceData[i].DiffuseColor = Color4.White;
startPosition = endPosition;
}
// Create tube mesh with normalized radius (=1) and from (0,0,0) to (1,0,0).
// This mesh is then transformed to connect positions along the path
var tubeLineMesh3D = new Ab3d.Meshes.TubeLineMesh3D(startPosition: new Point3D(0, 0, 0),
endPosition: new Point3D(1, 0, 0),
radius: 1,
segments: 8,
generateTextureCoordinates: false).Geometry;
// Create InstancedMeshGeometryVisual3D
var instancedMeshGeometryVisual3D = new InstancedMeshGeometryVisual3D(tubeLineMesh3D);
instancedMeshGeometryVisual3D.InstancesData = instanceData;
// Set IsSolidColorMaterial to render tube instances with solid color without any shading based on lighting
instancedMeshGeometryVisual3D.IsSolidColorMaterial = true;
// Add instancedMeshGeometryVisual3D to the scene
MainViewport.Children.Add(instancedMeshGeometryVisual3D);
return(instancedMeshGeometryVisual3D);
}
private InstanceData[] CreateInstancesData(Point3D center, Size3D size, int xCount, int yCount, int zCount)
{
var instancedData = new InstanceData[xCount * yCount * zCount];
float xStep = (float)(size.X / xCount);
float yStep = (float)(size.Y / yCount);
float zStep = (float)(size.Z / zCount);
int i = 0;
for (int z = 0; z < zCount; z++)
{
float zPos = (float)(center.Z - (size.Z / 2.0) + (z * zStep));
for (int y = 0; y < yCount; y++)
{
float yPos = (float)(center.Y - (size.Y / 2.0) + (y * yStep));
for (int x = 0; x < xCount; x++)
{
float xPos = (float)(center.X - (size.X / 2.0) + (x * xStep));
instancedData[i].World = SharpDX.Matrix.Translation(xPos, yPos, zPos);
// If we would also need to scale the mesh, we could create the matrix with the following code:
//instancedData[i].World = new SharpDX.Matrix(xScale, 0, 0, 0,
// 0, yScale, 0, 0,
// 0, 0, zScale, 0,
// xPos, yPos, zPos, 1);
//instancedData[i].DiffuseColor = new SharpDX.Color4(new SharpDX.Color3(0.3f + ((float)x / (float)xCount) * 0.7f,
// 0.3f + ((float)y / (float)yCount) * 0.7f,
// 0.3f + ((float)y / (float)yCount) * 0.7f));
instancedData[i].DiffuseColor = new SharpDX.Color4(new SharpDX.Color3(0.1f + ((float)y / (float)yCount) * 0.9f,
(float)Math.Abs(0.5 - ((float)x / (float)xCount)) * 2.0f,
0.1f + ((float)(yCount - y) / (float)yCount) * 0.9f));
// Use WPF's Orange color:
//instancedData[i].Color = Colors.Orange.ToColor4();
i++;
}
}
}
return(instancedData);
}
private void CreateInstancedTubePath()
{
// Create curve through those points
var controlPoints = new Point3D[]
{
new Point3D(-200, 50, 150),
new Point3D(0, 50, 20),
new Point3D(150, 50, 0),
new Point3D(150, 50, 200),
new Point3D(250, 50, 200)
};
// To create curve through specified points we must first convert the points into a bezierCurve (curve that has tangents defined for each point).
// The curve is created with 10 points per segments - 10 points between two control points.
var bezierCurve = Ab3d.Utilities.BezierCurve.CreateFromCurvePositions(controlPoints);
var curvePositions = bezierCurve.CreateBezierCurve(positionsPerSegment: 10);
// Convert Point3D to Vector3
var dxCurvePositions = curvePositions.Select(p => p.ToVector3()).ToList();
// Setup InstanceData
var instanceData = new InstanceData[curvePositions.Count];
// NOTE:
// When a tube path is created from a lot of positions,
// then it is worth to transform the following loop into Parallel.For loop.
var startPosition = dxCurvePositions[0];
for (int i = 1; i < dxCurvePositions.Count; i++)
{
var endPosition = dxCurvePositions[i];
var direction = endPosition - startPosition;
var length = direction.Length(); // length will be used for x scale
var scale = new Vector3(length, 1, 1);
//direction.Normalize(); // Because we already have length, we can quickly normalize with simply dividing by length
direction /= length;
instanceData[i].World = Common.MatrixUtils.GetMatrixFromNormalizedDirection(direction, startPosition, scale);
instanceData[i].DiffuseColor = Color4.White;
startPosition = endPosition;
}
// Create tube mesh with normalized radius (=1) and from (0,0,0) to (1,0,0).
// This mesh is then transformed to connect positions along the path
var tubeLineMesh3D = new Ab3d.Meshes.TubeLineMesh3D(startPosition: new Point3D(0, 0, 0),
endPosition: new Point3D(1, 0, 0),
radius: 1,
segments: 8,
generateTextureCoordinates: false).Geometry;
// Create InstancedMeshGeometryVisual3D
var instancedMeshGeometryVisual3D = new InstancedMeshGeometryVisual3D(tubeLineMesh3D);
instancedMeshGeometryVisual3D.InstancesData = instanceData;
// Set IsSolidColorMaterial to render tube instances with solid color without any shading based on lighting
instancedMeshGeometryVisual3D.IsSolidColorMaterial = true;
// Add instancedMeshGeometryVisual3D to the scene
MainViewport.Children.Add(instancedMeshGeometryVisual3D);
}
