public GraphicsTriangle(Triangle triangle)
{
Points = new GraphicsVector3[3];
TexturePoints = new TextureVector[3];
for (int i = 0; i < 3; ++i)
{
Points[i] = new GraphicsVector3(triangle.Points[i]);
TexturePoints[i] = new TextureVector();
}
Normal = triangle.Normal;
Color = triangle.Color;
}
public GraphicsTriangle(GraphicsVector3 point1, GraphicsVector3 point2, GraphicsVector3 point3, TextureVector texturePoint1, TextureVector texturePoint2, TextureVector texturePoint3, Vector3 normal, Color color)
{
Points = new GraphicsVector3[3];
Points[0] = point1;
Points[1] = point2;
Points[2] = point3;
TexturePoints = new TextureVector[3];
TexturePoints[0] = texturePoint1;
TexturePoints[1] = texturePoint2;
TexturePoints[2] = texturePoint3;
Normal = normal;
Color = color;
}
public GraphicsTriangle Copy()
{
GraphicsVector3[] newPoints = new GraphicsVector3[3];
TextureVector[] newTexturePoints = new TextureVector[3];
for (int i = 0; i < 3; ++i)
{
newPoints[i] = new GraphicsVector3(Points[i]);
newTexturePoints[i] = new TextureVector(TexturePoints[i]);
}
return(new GraphicsTriangle(newPoints, newTexturePoints, Normal, Color));
}
private TextureVector clipTextureVector(TextureVector insidePoint, TextureVector outsidePoint, float t)
{
return(new TextureVector(t * (outsidePoint.U - insidePoint.U) + insidePoint.U, t * (outsidePoint.V - insidePoint.V) + insidePoint.V, t * (outsidePoint.W - insidePoint.W) + insidePoint.W));
}
private GraphicsTriangle[] ClipTriangleAgainstPlane(Vector3 planePosition, Vector3 planeNormal, GraphicsTriangle triangle)
{
planeNormal = Vector3.Normalize(planeNormal);
List <GraphicsVector3> insidePoints = new List <GraphicsVector3>();
List <GraphicsVector3> outsidePoints = new List <GraphicsVector3>();
List <TextureVector> insideTexturePoints = new List <TextureVector>();
List <TextureVector> outsideTexturePoints = new List <TextureVector>();
float[] distances = new float[3];
for (int i = 0; i < 3; ++i)
{
distances[i] = GetShortestDistanceToPlane(triangle.Points[i], planePosition, planeNormal);
}
for (int i = 0; i < 3; ++i)
{
if (distances[i] >= 0)
{
insidePoints.Add(triangle.Points[i]);
insideTexturePoints.Add(triangle.TexturePoints[i]);
}
else
{
outsidePoints.Add(triangle.Points[i]);
outsideTexturePoints.Add(triangle.TexturePoints[i]);
}
}
if (insidePoints.Count == 0)
{
return(new GraphicsTriangle[] { });
}
if (insidePoints.Count == 3)
{
return(new GraphicsTriangle[] { triangle });
}
if (insidePoints.Count == 1 && outsidePoints.Count == 2)
{
GraphicsVector3 p1 = insidePoints[0];
TextureVector tp1 = insideTexturePoints[0];
float t;
GraphicsVector3 p2 = LinePlaneIntersection(planePosition, planeNormal, p1, outsidePoints[0], out t);
TextureVector tp2 = clipTextureVector(insideTexturePoints[0], outsideTexturePoints[0], t);
GraphicsVector3 p3 = LinePlaneIntersection(planePosition, planeNormal, p1, outsidePoints[1], out t);
TextureVector tp3 = clipTextureVector(insideTexturePoints[0], outsideTexturePoints[1], t);
return(new GraphicsTriangle[] { new GraphicsTriangle(p1, p2, p3, tp1, tp2, tp3, triangle.Normal, triangle.Color) });
}
if (insidePoints.Count == 2 && outsidePoints.Count == 1)
{
float t;
GraphicsVector3 t1p1 = insidePoints[0];
GraphicsVector3 t1p2 = insidePoints[1];
GraphicsVector3 t1p3 = LinePlaneIntersection(planePosition, planeNormal, t1p1, outsidePoints[0], out t);
TextureVector t1tp1 = insideTexturePoints[0];
TextureVector t1tp2 = insideTexturePoints[1];
TextureVector t1tp3 = clipTextureVector(t1tp1, outsideTexturePoints[0], t);
GraphicsVector3 t2p1 = insidePoints[1];
GraphicsVector3 t2p2 = t1p3;
GraphicsVector3 t2p3 = LinePlaneIntersection(planePosition, planeNormal, t2p1, outsidePoints[0], out t);
TextureVector t2tp1 = insideTexturePoints[1];
TextureVector t2tp2 = t1tp3;
TextureVector t2tp3 = clipTextureVector(t2tp1, outsideTexturePoints[0], t);
return(new GraphicsTriangle[] {
new GraphicsTriangle(t1p1, t1p3, t1p2, t1tp1, t1tp2, t1tp3, triangle.Normal, triangle.Color),
new GraphicsTriangle(t2p1, t2p2, t2p3, t2tp1, t2tp2, t2tp3, triangle.Normal, triangle.Color)
});
}
return(null); //To satisfy the compliers :(
}
public TextureVector(TextureVector original)
{
U = original.U;
V = original.V;
W = original.W;
}
