static Terrain()
{
// Create the array of render batches
for (int i = 0; i < NUMTEXTURES; i++)
{
batch[i] = new RenderBatch(20);
}
// Load the height map
using (Bitmap bmp = (Bitmap)Bitmap.FromFile(FileResource.Fsp("terrain", "terrainheight.bmp")))
{
// compute scale
gridWidth = bmp.Width-1; // the grid of tiles will be 1 smaller than
gridHeight = bmp.Height-1; // the grid of heights (last height = RH side of last tile)
tileWidth = (float)Map.MapWidth / gridWidth;
tileHeight = (float)Map.MapHeight / gridHeight;
// Create the blank tiles
tile = new Terrain[gridWidth,gridHeight];
// get heightmap into an array, for faster access
// (Note: bitmap's origin is at TOP-left, so flip Y. Tile grid's origin is bottom-left)
height = new float[bmp.Width,bmp.Height];
for (int y = 0; y<bmp.Height; y++)
{
for (int x=0; x<bmp.Width; x++)
{
height[x,y] = (float)bmp.GetPixel(x, bmp.Height-1-y).R * MAXHEIGHT / 256;
}
}
} // dispose of the bitmap
// Create the tiles and define their extents and heights
for (int y = 0; y<gridHeight; y++)
{
for (int x=0; x<gridWidth; x++)
{
tile[x,y] = new Terrain(x,y,tileWidth,tileHeight,ref height);
}
}
// Now that the triangles exist, define the vertex normals, by averaging the
// surface normals of surrounding triangles
for (int y = 1; y<gridHeight-1; y++)
{
for (int x=1; x<gridWidth-1; x++)
{
SetVertexNormal(tile,x,y);
}
}
/// TODO: Load the texture map here & set the tiles' texture #s
using (Bitmap bmp = (Bitmap)Bitmap.FromFile(FileResource.Fsp("terrain", "terraintex.bmp")))
{
for (int y = 0; y<gridHeight; y++)
{
for (int x=0; x<gridWidth; x++)
{
tile[x,y].texture = (int)((float)bmp.GetPixel(x,bmp.Height-1-y).R / 256.0f * NUMTEXTURES);
}
}
}
// Define a material for lighting the textures
// (May want different materials for each texture later?)
material.Ambient = Color.FromArgb(64,64,64);
material.Diffuse = Color.FromArgb(255, 255, 255);
material.Specular = Color.FromArgb(90, 90, 90);
}
/// <summary>
/// Set the vertex normals for the triangles in this tile.
/// Each vertex normal is the average of the face normals for surrounding triangles
/// (some of which are in different tiles)
/// </summary>
/// <param name="tile">the array of tiles</param>
/// <param name="x">our location in the array</param>
/// <param name="y"></param>
public static void SetVertexNormal(Terrain[,] tile, int x, int y)
{
// NW vertex
tile[x,y].mesh[0].Normal = Vector3.Normalize(
tile[x-1,y+1].faceNormal[1]
+ tile[x,y+1].faceNormal[0]
+ tile[x,y+1].faceNormal[1]
+ tile[x,y].faceNormal[0]
+ tile[x-1,y].faceNormal[1]
+ tile[x-1,y].faceNormal[0]
);
// NE vertex
tile[x,y].mesh[1].Normal = Vector3.Normalize(
tile[x,y+1].faceNormal[1]
+ tile[x+1,y+1].faceNormal[0]
+ tile[x+1,y+1].faceNormal[1]
+ tile[x+1,y].faceNormal[0]
+ tile[x,y].faceNormal[1]
+ tile[x,y].faceNormal[0]
);
// SW vertex
tile[x,y].mesh[2].Normal = Vector3.Normalize(
tile[x-1,y].faceNormal[1]
+ tile[x,y].faceNormal[0]
+ tile[x,y].faceNormal[1]
+ tile[x,y-1].faceNormal[0]
+ tile[x-1,y-1].faceNormal[1]
+ tile[x-1,y-1].faceNormal[0]
);
// SE vertex
tile[x,y].mesh[3].Normal = Vector3.Normalize(
tile[x,y].faceNormal[1]
+ tile[x+1,y].faceNormal[0]
+ tile[x+1,y].faceNormal[1]
+ tile[x+1,y-1].faceNormal[0]
+ tile[x,y-1].faceNormal[1]
+ tile[x,y-1].faceNormal[0]
);
// Add tangent and binormal vectors calculated from vertex normals
for (int i = 0; i < 4; i++)
{
ThreeDee.TangentFromNormal(tile[x, y].mesh[i].Normal, out tile[x, y].mesh[i].Tangent, out tile[x, y].mesh[i].Binormal);
}
}
