#!/usr/bin/env python
# -*- coding: utf-8 -*-
"""
Example for using Helios DAC libraries in python (using C library with ctypes)

NB: If you haven't set up udev rules you need to use sudo to run the program for it to detect the DAC.
"""

import ctypes

#Define point structure
class HeliosPoint(ctypes.Structure):
    #_pack_=1
    _fields_ = [('x', ctypes.c_uint16),
                ('y', ctypes.c_uint16),
                ('r', ctypes.c_uint8),
                ('g', ctypes.c_uint8),
                ('b', ctypes.c_uint8),
                ('i', ctypes.c_uint8)]

#Load and initialize library
HeliosLib = ctypes.cdll.LoadLibrary("./libHeliosDacAPI.dylib")
numDevices = HeliosLib.OpenDevices()

#WriteFrame(unsigned int dacNum, int pps, std::uint8_t flags, HeliosPoint* points, int numOfPoints);
#in 1024 points:
#scale up x from 0 to 100%
#scale down y from 0 to 100%
#scale R, G and B up from 0 to 255 4 times out of sync

frames=[0 for x in range(1024)]
r=0
g=85
b=170

def inc8(m):
    return (m+1)%256

for i in range(1024):
    frames[i]=HeliosPoint(i*16,16383-(i*16),r,g,b,0)
    r=inc8(r)
    g=inc8(g)
    b=inc8(b)

try:
    while True:
        HeliosLib.WriteFrame(0, 20000, 0, ctypes.pointer(frames[0]), 1024)
except KeyboardInterrupt:
    pass

HeliosLib.CloseDevices()