private void CreateRivers()
{
for (int i = 0; i < bounds.width / 2; i++)
{
Corner c = corners[r.Next(corners.Count)];
if (c.ocean || c.elevation < 0.3 || c.elevation > 0.9)
{
continue;
}
if (r.Next(5) != 0)
{
continue;
}
while (!c.coast)
{
if (c == c.downslope)
{
break;
}
DEdge dE = LookupEdgeFromCorner(c, c.downslope);
if (!dE.v0.water || !dE.v1.water)
{
dE.river++;
c.river++;
c.downslope.river++;
}
c = c.downslope;
}
}
}
// Draws a voronoi polygon
private void DrawPolygon(System.Drawing.Graphics g, Center c, System.Drawing.Color color, bool noisyEdges, bool smoothBlending, bool lighting, bool drawBiomes)
{
Corner eC1 = null;
Corner eC2 = null;
c.area = 0;
foreach (Center n in c.neighbors)
{
DEdge e = EdgeWithCenters(c, n);
//Experimental Color (Biome Blending)
if (smoothBlending && drawBiomes)
{
color = BlendBiome(color, c, n);
}
//Experimental Lighting (Light Vectors)
if (lighting && drawBiomes)
{
color = ColorWithSlope(color, c, n, e);
}
// If noisy edges is off, draw triangles to create voronoi polygons (center to vertices of each edge)
if (!noisyEdges)
{
if (e.v0 == null)
{
continue;
}
Corner corner1A = e.v0.border ? e.v0 : e.v1;
if (corner1A.border)
{
if (eC1 == null)
{
eC1 = corner1A;
}
else
{
eC2 = corner1A;
}
}
DrawTriangle(g, e.v0, e.v1, c, color);
c.area = Math.Abs(c.loc.x * (e.v0.loc.y - e.v1.loc.y)
+ e.v0.loc.x * (e.v1.loc.y - c.loc.y)
+ e.v1.loc.x * (c.loc.y - e.v0.loc.y)) / 2;
}
//Experimental Polygon Drawing using noisy (natural) edges
if (noisyEdges)
{
// For each of the noisy edge paths fill the polygon created betweeen them and the center
if (path0[e.index] != null)
{
List <Point> tPath = path0[e.index];
System.Drawing.Point[] tA = new System.Drawing.Point[tPath.Count + 2];
tA[0] = new System.Drawing.Point((int)c.loc.x, (int)c.loc.y);
for (int i = 0; i < tPath.Count; i++)
{
tA[i + 1] = new System.Drawing.Point((int)tPath[i].x, (int)tPath[i].y);
}
tA[tA.Count() - 1] = new System.Drawing.Point((int)c.loc.x, (int)c.loc.y);
g.FillPolygon(new System.Drawing.SolidBrush(color), tA);
}
if (path1[e.index] != null)
{
List <Point> tPath = path1[e.index];
System.Drawing.Point[] tA = new System.Drawing.Point[tPath.Count + 2];
tA[0] = new System.Drawing.Point((int)c.loc.x, (int)c.loc.y);
for (int i = 0; i < tPath.Count; i++)
{
tA[i + 1] = new System.Drawing.Point((int)tPath[i].x, (int)tPath[i].y);
}
tA[tA.Count() - 1] = new System.Drawing.Point((int)c.loc.x, (int)c.loc.y);
g.FillPolygon(new System.Drawing.SolidBrush(color), tA);
}
}
}
if (eC2 != null)
{
if (CloseEnough(eC1.loc.x, eC2.loc.x, 1))
{
DrawTriangle(g, eC1, eC2, c, color);
}
else
{
System.Drawing.Point[] points = new System.Drawing.Point[4];
points[0] = new System.Drawing.Point((int)c.loc.x, (int)c.loc.y);
points[1] = new System.Drawing.Point((int)eC1.loc.x, (int)eC1.loc.y);
int tX = (int)((CloseEnough(eC1.loc.x, bounds.x, 1) || CloseEnough(eC2.loc.x, bounds.x, 0.5)) ? bounds.x : bounds.right);
int tY = (int)((CloseEnough(eC1.loc.y, bounds.y, 1) || CloseEnough(eC2.loc.y, bounds.y, 0.5)) ? bounds.y : bounds.bottom);
points[2] = new System.Drawing.Point(tX, tY);
points[3] = new System.Drawing.Point((int)eC2.loc.x, (int)eC2.loc.y);
g.FillPolygon(new System.Drawing.SolidBrush(color), points);
c.area += 0;
}
}
}
private void BuildGraph(Voronoi v)
{
Dictionary <Point, Center> pCMap = new Dictionary <Point, Center>();
List <Point> points = v.SiteCoords();
// For each point create a center
foreach (Point p in points)
{
Center c = new Center();
c.loc = p;
c.index = centers.Count;
centers.Add(c);
pCMap[p] = c;
}
// For each center, assign a region
foreach (Center c in centers)
{
v.Region(c.loc);
}
List <Edge> libEdges = v.Edges();
Dictionary <int, Corner> pCRMap = new Dictionary <int, Corner>();
// For each edge in the voronoi edges
foreach (Edge e in libEdges)
{
LineSegment vEdge = e.VoronoiEdge();
LineSegment dEdge = e.DelaunayLine();
DEdge dE = new DEdge();
dE.index = edges.Count;
edges.Add(dE);
// Setup midpoints for viable voronoi edges for noisy edge generation
if (vEdge.p0 != null && vEdge.p1 != null)
{
dE.midPoint = InterpolatePoint(vEdge.p0, vEdge.p1, 0.5);
}
// Create corners for the voronoi vertices of the edge
dE.v0 = MakeCorner(pCRMap, vEdge.p0);
dE.v1 = MakeCorner(pCRMap, vEdge.p1);
dE.d0 = pCMap[dEdge.p0];
dE.d1 = pCMap[dEdge.p1];
// Add borders for delaunay edges
if (dE.d0 != null)
{
dE.d0.borders.Add(dE);
}
if (dE.d1 != null)
{
dE.d1.borders.Add(dE);
}
if (dE.v0 != null)
{
dE.v0.protrudes.Add(dE);
}
if (dE.v1 != null)
{
dE.v1.protrudes.Add(dE);
}
if (dE.d0 != null && dE.d1 != null)
{
AddToCenterList(dE.d0.neighbors, dE.d1);
AddToCenterList(dE.d1.neighbors, dE.d0);
}
if (dE.v0 != null && dE.v1 != null)
{
AddToCornerList(dE.v0.adjacent, dE.v1);
AddToCornerList(dE.v1.adjacent, dE.v0);
}
if (dE.d0 != null)
{
AddToCornerList(dE.d0.corners, dE.v0);
AddToCornerList(dE.d0.corners, dE.v1);
}
if (dE.d1 != null)
{
AddToCornerList(dE.d1.corners, dE.v0);
AddToCornerList(dE.d1.corners, dE.v1);
}
if (dE.v0 != null)
{
AddToCenterList(dE.v0.touches, dE.d0);
AddToCenterList(dE.v0.touches, dE.d1);
}
if (dE.v1 != null)
{
AddToCenterList(dE.v1.touches, dE.d0);
AddToCenterList(dE.v1.touches, dE.d1);
}
}
}
public System.Drawing.Color ColorWithSlope(System.Drawing.Color c, Center p, Center q, DEdge e)
{
Corner r = e.v0;
Corner s = e.v1;
if (r == null || s == null)
{
return(c);
}
else if (p.water)
{
return(c);
}
if (q != null && p.water == q.water)
{
c = InterpolateColor(c, GetColor(q.biome), 0.4);
}
System.Drawing.Color low = InterpolateColor(c, System.Drawing.Color.FromArgb(51, 51, 51), 0.7);
System.Drawing.Color high = InterpolateColor(c, System.Drawing.Color.FromArgb(255, 255, 255), 0.3);
double light = CalculateLighting(p, r, s);
if (light < 0.5)
{
return(InterpolateColor(low, c, light * 2));
}
else
{
return(InterpolateColor(c, high, light * 2 - 1));
}
}