public static SDFGrid FromTexture(Texture texture)
{
var grid = new SDFGrid(texture.Width, texture.Height);
const int EMPTY = 9999;
if (texture.Format.SizeInBytes() != 4)
{
Debug.Log("Don't compress the textures!!");
}
byte[] data = texture.GetMipData(0, out int rowPitch, out int slicePitch);
unsafe
{
fixed(byte *dataPtr = data)
{
var colorsPtr = (Color32 *)dataPtr;
for (int y = 0; y < texture.Height; y++)
{
for (int x = 0; x < texture.Width; x++)
{
var color = colorsPtr[y * texture.Width + x];
int dist = (int)(color.R > 128 + 50 ? EMPTY : 0);
grid._gridPos[x + 1, y + 1] = new Int2(dist);
grid._gridNeg[x + 1, y + 1] = new Int2(EMPTY - dist);
}
}
}
}
int gridWidth = grid._gridPos.GetLength(0);
int gridHeight = grid._gridPos.GetLength(1);
for (int i = 0; i < gridWidth; i++)
{
grid._gridPos[i, 0] = new Int2(0);
grid._gridNeg[i, 0] = new Int2(EMPTY);
grid._gridPos[i, gridHeight - 1] = new Int2(0);
grid._gridNeg[i, gridHeight - 1] = new Int2(EMPTY);
}
for (int i = 0; i < gridHeight; i++)
{
grid._gridPos[0, i] = new Int2(0);
grid._gridNeg[0, i] = new Int2(EMPTY);
grid._gridPos[gridWidth - 1, i] = new Int2(0);
grid._gridNeg[gridWidth - 1, i] = new Int2(EMPTY);
}
var positiveOffsets = new[]
{
new Int2(-1, 0),
new Int2(0, -1),
new Int2(-1, -1),
new Int2(1, -1)
};
grid.RunPass(grid._gridPos, positiveOffsets, new Int2(1, 0), false);
grid.RunPass(grid._gridNeg, positiveOffsets, new Int2(1, 0), false);
var negativeOffsets = new[]
{
new Int2(1, 0),
new Int2(0, 1),
new Int2(-1, 1),
new Int2(1, 1)
};
grid.RunPass(grid._gridPos, negativeOffsets, new Int2(-1, 0), true);
grid.RunPass(grid._gridNeg, negativeOffsets, new Int2(-1, 0), true);
return(grid);
}
/// <summary>
/// Converts a black and white image to a SDF
/// </summary>
public static Texture BlackAndWhiteToSDF(Texture texture, float spreadRadius)
{
SDFGrid grid = SDFGrid.FromTexture(texture);
return(grid.ToTexture(spreadRadius));
}
