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int CTerrain::SetupTerrainBlocks(void)
{
	unsigned int currentVertex, numBlockPolys;
	
	numBlockPolys = BLOCK_SIZE - 1;	// Always 1 less polygon for n vertices

	
	// Loop across each terrain block

	for (int z = 0; z < mapheight / numBlockPolys; z++)
		for (int x = 0; x < mapwidth / numBlockPolys; x++)
		{
			mapblocks[x][z] = new TerrainBlock;
			int index = 0;

			// Setup the indexing info for this map block

			for (int z2 = 0; z2 < BLOCK_SIZE -1; z2++)
				for (int x2 = 0; x2 < BLOCK_SIZE; x2++)
				{
					// Move to the correct block

					currentVertex = z * numBlockPolys * mapwidth + x * numBlockPolys;
					// Move to the correct offset within the block

					currentVertex += z2 * mapwidth + x2;
			
					mapblocks[x][z]->indexArray[0][index++] = currentVertex + mapwidth;
					mapblocks[x][z]->indexArray[0][index++] = currentVertex;
				}
		}
	
	return(OK);
}

glEnableClientState(GL_VERTEX_ARRAY);
glEnableClientState(GL_COLOR_ARRAY);
glEnableClientState(GL_TEXTURE_COORD_ARRAY);

glVertexPointer(3, GL_FLOAT, 0, terrain);
glTexCoordPointer(2, GL_FLOAT, 0, texcoords);
glColorPointer(3, GL_FLOAT, 0, colors);

for (int z = 0; z < mapheight / (BLOCK_SIZE - 1); z++)
for (int x = 0; x < mapwidth / (BLOCK_SIZE -1); x++)
DrawTerrainBlock(mapblocks[x][z]);

glDisableClientState(GL_VERTEX_ARRAY);
glDisableClientState(GL_COLOR_ARRAY);
glDisableClientState(GL_TEXTURE_COORD_ARRAY);

int CTerrain::DrawTerrainBlock(TerrainBlock *block)
{
	// Do frustum culling!

	if (!CheckBlockVisibility(block))
		return(OK);

	int mipmaplevel = 0;
	int mipmapHeight, mipmapWidth;
	
	// Set the size of the terrain block depending on the mipmap level

	mipmapHeight = (BLOCK_SIZE -1) / pow(2, mipmaplevel) + 1;
	mipmapWidth = mipmapHeight;
	
	glEnable(GL_CULL_FACE);
	
	glPolygonMode(GL_FRONT, GL_LINE);
	
	glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR );
	glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR );
	
	unsigned int tex = GetEngine()->GetGraphics()->GetTextureManager()->GetSurface(TEX_GRASS_1);
	glBindTexture(GL_TEXTURE_2D, tex);
	
	for (int z = 0; z < mipmapHeight - 1; z++)
		glDrawElements(GL_TRIANGLE_STRIP, mipmapWidth * 2, GL_UNSIGNED_INT, 
						&block->indexArray[mipmaplevel][z * mipmapWidth * 2]);
	
	glPolygonMode(GL_FRONT, GL_FILL);
		
	return(0);
}