acid-drop

- Hacking the planet from a LilyGo T-Deck using custom firmware
git clone git://git.acid.vegas/acid-drop.git
lv_example_chart_7.py (2410B)
      1 #!/opt/bin/lv_micropython -i
      2 import utime as time
      3 import lvgl as lv
      4 import display_driver
      5 
      6 def draw_event_cb(e):
      7     dsc = e.get_draw_part_dsc()
      8     if dsc.part == lv.PART.ITEMS:
      9         obj = e.get_target()
     10         ser = obj.get_series_next(None)
     11         cnt = obj.get_point_count()
     12         # print("cnt: ",cnt)
     13         # Make older value more transparent
     14         dsc.rect_dsc.bg_opa = (lv.OPA.COVER *  dsc.id) // (cnt - 1)
     15 
     16         # Make smaller values blue, higher values red
     17         # x_array = chart.get_x_array(ser)
     18         # y_array = chart.get_y_array(ser)
     19         # dsc->id is the tells drawing order, but we need the ID of the point being drawn.
     20         start_point = chart.get_x_start_point(ser)
     21         # print("start point: ",start_point)
     22         p_act = (start_point + dsc.id) % cnt # Consider start point to get the index of the array
     23         # print("p_act", p_act)
     24         x_opa = (x_array[p_act] * lv.OPA._50) // 200
     25         y_opa = (y_array[p_act] * lv.OPA._50) // 1000
     26 
     27         dsc.rect_dsc.bg_color = lv.palette_main(lv.PALETTE.RED).color_mix(
     28                                              lv.palette_main(lv.PALETTE.BLUE),
     29                                              x_opa + y_opa)
     30 
     31 def add_data(timer,chart):
     32     # print("add_data")
     33     x = lv.rand(0,200)
     34     y = lv.rand(0,1000)
     35     chart.set_next_value2(ser, x, y)
     36     # chart.set_next_value2(chart.gx, y)
     37     x_array.pop(0)
     38     x_array.append(x)
     39     y_array.pop(0)
     40     y_array.append(y)
     41 
     42 #
     43 # A scatter chart
     44 #
     45 
     46 chart = lv.chart(lv.scr_act())
     47 chart.set_size(200, 150)
     48 chart.align(lv.ALIGN.CENTER, 0, 0)
     49 chart.add_event_cb(draw_event_cb, lv.EVENT.DRAW_PART_BEGIN, None)
     50 chart.set_style_line_width(0, lv.PART.ITEMS)   # Remove the lines
     51 
     52 chart.set_type(lv.chart.TYPE.SCATTER)
     53 
     54 chart.set_axis_tick(lv.chart.AXIS.PRIMARY_X, 5, 5, 5, 1, True, 30)
     55 chart.set_axis_tick(lv.chart.AXIS.PRIMARY_Y, 10, 5, 6, 5, True, 50)
     56 
     57 chart.set_range(lv.chart.AXIS.PRIMARY_X, 0, 200)
     58 chart.set_range(lv.chart.AXIS.PRIMARY_Y, 0, 1000)
     59 
     60 chart.set_point_count(50)
     61 
     62 ser = chart.add_series(lv.palette_main(lv.PALETTE.RED), lv.chart.AXIS.PRIMARY_Y)
     63 
     64 x_array = []
     65 y_array = []
     66 for i in range(50):
     67     x_array.append(lv.rand(0, 200))
     68     y_array.append(lv.rand(0, 1000))
     69 
     70 ser.x_points = x_array
     71 ser.y_points = y_array
     72 
     73 # Create an `lv_timer` to update the chart.
     74 
     75 timer = lv.timer_create_basic()
     76 timer.set_period(100)
     77 timer.set_cb(lambda src: add_data(timer,chart))