Iterate through a player's current chunk in minecraft forge
EntityPlayer player = Minecraft.getMinecraft().player;
World world = player.getEntityWorld();
Chunk chunk = world.getChunkFromBlockCoords(player.getPosition());
for ( double x = 0; x <= 15; x++) {
for( double y = 0; y <= 255; y++ ) {
for( double z = 0; z <= 15; z++ ) {
BlockPos actualPosition = new BlockPos(x,y,z);
IBlockState state = chunk.getBlockState(actualPosition);
//do stuff
}
}
}