private void DrawLightEdge(LightEdge e, Color col)
{
// debug light edges
Vector3 p0 = cam.WorldToScreenPoint(new Vector3(e.x1, e.y1, 0));
Vector3 p1 = cam.WorldToScreenPoint(new Vector3(e.x2, e.y2, 0));
DrawLine(lightTexture, (int)p0.x, (int)p0.y, (int)p1.x, (int)p1.y, col);
Debug.DrawLine(new Vector3(e.x1, e.y1, 0), new Vector3(e.x2, e.y2, 0), col);
if (e.prev != null)
{
//DrawLine(lightTexture, (int)p0.x - 5, (int)p0.y - 5, (int)p0.x + 5, (int)p0.y + 5, Color.magenta);
}
if (e.next != null)
{
//DrawLine(lightTexture, (int)p1.x + 5, (int)p1.y - 5, (int)p1.x - 5, (int)p1.y + 5, new Color(1f, 1f, 1, 1));
//DrawLine(lightTexture, (int)p1.x - 5, (int)p1.y - 5, (int)p1.x + 5, (int)p1.y + 5, Color.white);
}
}
private float DistancePointToEdge(float x, float y, LightEdge e)
{
float x1 = e.x1;
float y1 = e.y1;
float x2 = e.x2;
float y2 = e.y2;
float A = x - x1;
float B = y - y1;
float C = x2 - x1;
float D = y2 - y1;
float dot = A * C + B * D;
float len_sq = C * C + D * D;
float param = -1.0f;
if (len_sq != 0)
{
param = dot / len_sq;
}
float xx, yy;
if (param < 0)
{
xx = x1;
yy = y1;
}
else if (param > 1)
{
xx = x2;
yy = y2;
}
else
{
xx = x1 + param * C;
yy = y1 + param * D;
}
var dx = x - xx;
var dy = y - yy;
return(Mathf.Sqrt(dx * dx + dy * dy));
}
private float LightEdgesIntersect(LightEdge a, LightEdge b)
{
float ua, ub, ud, ux, uy, vx, vy, wx, wy;
ua = 0.0f;
ux = a.x2 - a.x1;
uy = a.y2 - a.y1;
vx = b.x2 - b.x1;
vy = b.y2 - b.y1;
wx = a.x1 - b.x1;
wy = a.y1 - b.y1;
ud = vy * ux - vx * uy;
if (ud != 0)
{
ua = (vx * wy - vy * wx) / ud;
ub = (ux * wy - uy * wx) / ud;
if (ua < 0 || ua > 1 || ub < 0 || ub > 1)
{
ua = 0;
}
}
return(ua);
}
public void GetLightEdges(Rect bounds, float x, float y)
{
PriorityQueue <LightEdge> edges = new PriorityQueue <LightEdge>();
float leftX = Mathf.FloorToInt(bounds.x);
float rightX = Mathf.FloorToInt(bounds.x + bounds.width) + 1;
float botY = Mathf.FloorToInt(bounds.y);
float topY = Mathf.FloorToInt(bounds.y + bounds.height) + 1;
// find all edges facing (x, y) in the bounds
int leftCol = Mathf.FloorToInt(leftX / CELL_SIZE);
leftCol = Mathf.Clamp(leftCol, 0, Cave.grid.GetLength(0) - 1);
int rightCol = Mathf.FloorToInt(rightX / CELL_SIZE) - 1;
rightCol = Mathf.Clamp(rightCol, 0, Cave.grid.GetLength(0) - 1);
int topRow = Mathf.FloorToInt(topY / CELL_SIZE) - 1;
topRow = Mathf.Clamp(topRow, -Cave.grid.GetLength(1) + 1, 0);
int botRow = Mathf.FloorToInt(botY / CELL_SIZE);
botRow = Mathf.Clamp(botRow, -Cave.grid.GetLength(1) + 1, 0);
// false means searching for end point
// true means searching for start point
bool firstIteration = true;
for (int r = botRow; r <= topRow; r++)
{
#region Set Left and Right Boundary Edges
Cell leftCell = Cave.grid[leftCol, -r];
if (leftCell == Cell.Empty || leftCell == Cell.SlantSW || leftCell == Cell.SlantNW)
{
LightEdge e = new LightEdge(leftCol, r, leftCol, r + 1);
e.distance = DistancePointToEdge(x, y, e);
edges.Enqueue(e);
}
Cell rightCell = Cave.grid[rightCol, -r];
if (rightCell == Cell.Empty || rightCell == Cell.SlantSE || rightCell == Cell.SlantNE)
{
LightEdge e = new LightEdge(rightX, r + 1, rightX, r);
e.distance = DistancePointToEdge(x, y, e);
edges.Enqueue(e);
}
#endregion
for (int c = leftCol; c <= rightCol; c++)
{
#region Set Top and Bottom Boundary Edges
if (firstIteration)
{
Cell topCell = Cave.grid[c, -topRow];
if (topCell == Cell.Empty || topCell == Cell.SlantNE || topCell == Cell.SlantNW)
{
LightEdge e = new LightEdge(c, topY, c + 1, topY);
e.distance = DistancePointToEdge(x, y, e);
edges.Enqueue(e);
}
Cell botCell = Cave.grid[c, -botRow];
if (botCell == Cell.Empty || botCell == Cell.SlantSE || botCell == Cell.SlantSW)
{
LightEdge e = new LightEdge(c + 1, botRow, c, botRow);
e.distance = DistancePointToEdge(x, y, e);
edges.Enqueue(e);
}
}
#endregion
LightEdge ee = GetCellEdgeFacingPoint(c, r, x, y);
if (ee != null)
{
ee.distance = DistancePointToEdge(x, y, ee);
edges.Enqueue(ee);
}
}
firstIteration = false;
}
foreach (LightEdge e in edges.getData())
{
// set next and previous edge values
foreach (LightEdge b in edges.getData())
{
if (!e.Equals(b))
{
if (e.x1 == b.x2 && e.y1 == b.y2)
{
e.prev = b;
b.next = e;
}
if (e.x2 == b.x1 && e.y2 == b.y1)
{
e.next = b;
b.prev = e;
}
}
}
}
List <LightEdge> pedges = new List <LightEdge>();
foreach (LightEdge e in edges.getData())
{
// set projections
if (e.prev == null)
{
Vector2 dir = new Vector2(e.x1 - x, e.y1 - y);
Vector2 line = dir.normalized * cam.orthographicSize * 10f;
LightEdge proj = new LightEdge(e.x1 + line.x, e.y1 + line.y, e.x1, e.y1);
proj.next = e;
proj.prev = null;
e.prev = proj;
// intersection logic
float pmag = (new Vector2(proj.x2 - proj.x1, proj.y2 - proj.x1)).magnitude;
foreach (LightEdge le in edges.getData())
{
float t = LightEdgesIntersect(le, proj);
Vector2 v = new Vector2(le.x2 - le.x1, le.y2 - le.y1);
v = v.normalized * v.magnitude * t;
float xi = le.x1 + v.x;
float yi = le.y1 + v.y;
float mag = Mathf.Sqrt(Mathf.Pow(proj.x2 - xi, 2) + Mathf.Pow(proj.y2 - yi, 2));
if (0 < t && t <= 1 && !le.Equals(e) && mag < pmag)
{
proj.prev = le;
le.next = proj;
proj.x1 = xi;
proj.y1 = yi;
le.x2 = xi;
le.y2 = yi;
pmag = mag;
}
}
proj.distance = DistancePointToEdge(x, y, proj);
pedges.Add(proj);
}
if (e.next == null)
{
Vector2 dir = new Vector2(e.x2 - x, e.y2 - y);
Vector2 line = dir.normalized * cam.orthographicSize * 10f;
LightEdge proj = new LightEdge(e.x2, e.y2, e.x2 + line.x, e.y2 + line.y);
proj.prev = e;
proj.next = null;
e.next = proj;
// intersection logic
float pmag = (new Vector2(proj.x2 - proj.x1, proj.y2 - proj.x1)).magnitude;
foreach (LightEdge le in edges.getData())
{
float t = LightEdgesIntersect(proj, le);
Vector2 v = new Vector2(proj.x2 - proj.x1, proj.y2 - proj.y1);
v = v.normalized * v.magnitude * t;
float xi = proj.x1 + v.x;
float yi = proj.y1 + v.y;
float mag = Mathf.Sqrt(Mathf.Pow(proj.x1 - xi, 2) + Mathf.Pow(proj.y1 - yi, 2));
if (0 < t && t <= 1 && !le.Equals(e) && mag < pmag)
{
proj.next = le;
le.prev = proj;
proj.x2 = xi;
proj.y2 = yi;
le.x1 = xi;
le.y1 = yi;
pmag = mag;
}
}
proj.distance = DistancePointToEdge(x, y, proj);
pedges.Add(proj);
}
}
// add projections to priority queue
foreach (LightEdge e in pedges)
{
edges.Enqueue(e);
}
// debug next and previous edge links
foreach (LightEdge e in edges.getData())
{
//DrawLightEdge(e, Color.red);
if (e.next != null)
{
// NEXT
DebugDrawSquare(e.x2, e.y2, 0.1f, Color.cyan);
}
else
{
DebugDrawSquare(e.x2, e.y2, 0.2f, Color.magenta);
DebugDrawSquare(e.x2, e.y2, 0.25f, Color.magenta);
}
if (e.prev != null)
{
// PREV
DebugDrawSquare(e.x1, e.y1, 0.05f, Color.green);
}
else
{
DebugDrawSquare(e.x1, e.y1, 0.2f, Color.magenta);
DebugDrawSquare(e.x1, e.y1, 0.25f, Color.magenta);
}
}
Mesh mesh = new Mesh();
MeshFilter filter = GetComponent <MeshFilter>();
int i = 0;
LightEdge light = edges.Peek();
List <Vector3> vertices = new List <Vector3>();
vertices.Add(new Vector3(x, y, 0));
do
{
vertices.Add(new Vector3(light.x1, light.y1, 0));
//DrawLightEdge(light, Color.green);
light = light.next;
i++;
} while (light != null && !light.Equals(edges.Peek()) && i < edges.getData().Count);
List <Int32> indices = new List <Int32>();
for (int v = 1; v < vertices.Count; v++)
{
indices.Add(0);
indices.Add(v);
int vv = v + 1;
if (vv >= vertices.Count)
{
vv = 1;
}
indices.Add(vv);
}
mesh.Clear();
mesh.SetVertices(vertices);
mesh.SetTriangles(indices, 0);
lightTexture.Apply();
filter.mesh = mesh;
}