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.c (2596B)
      1 #include "../../lv_examples.h"
      2 #if LV_USE_CHART && LV_BUILD_EXAMPLES
      3 
      4 static void draw_event_cb(lv_event_t * e)
      5 {
      6     lv_obj_draw_part_dsc_t * dsc = lv_event_get_draw_part_dsc(e);
      7     if(dsc->part == LV_PART_ITEMS) {
      8         lv_obj_t * obj = lv_event_get_target(e);
      9         lv_chart_series_t * ser = lv_chart_get_series_next(obj, NULL);
     10         uint32_t cnt = lv_chart_get_point_count(obj);
     11         /*Make older value more transparent*/
     12         dsc->rect_dsc->bg_opa = (LV_OPA_COVER *  dsc->id) / (cnt - 1);
     13 
     14         /*Make smaller values blue, higher values red*/
     15         lv_coord_t * x_array = lv_chart_get_x_array(obj, ser);
     16         lv_coord_t * y_array = lv_chart_get_y_array(obj, ser);
     17         /*dsc->id is the tells drawing order, but we need the ID of the point being drawn.*/
     18         uint32_t start_point = lv_chart_get_x_start_point(obj, ser);
     19         uint32_t p_act = (start_point + dsc->id) % cnt; /*Consider start point to get the index of the array*/
     20         lv_opa_t x_opa = (x_array[p_act] * LV_OPA_50) / 200;
     21         lv_opa_t y_opa = (y_array[p_act] * LV_OPA_50) / 1000;
     22 
     23         dsc->rect_dsc->bg_color = lv_color_mix(lv_palette_main(LV_PALETTE_RED),
     24                                                lv_palette_main(LV_PALETTE_BLUE),
     25                                                x_opa + y_opa);
     26     }
     27 }
     28 
     29 static void add_data(lv_timer_t * timer)
     30 {
     31     LV_UNUSED(timer);
     32     lv_obj_t * chart = timer->user_data;
     33     lv_chart_set_next_value2(chart, lv_chart_get_series_next(chart, NULL), lv_rand(0, 200), lv_rand(0, 1000));
     34 }
     35 
     36 /**
     37  * A scatter chart
     38  */
     39 void lv_example_chart_7(void)
     40 {
     41     lv_obj_t * chart = lv_chart_create(lv_scr_act());
     42     lv_obj_set_size(chart, 200, 150);
     43     lv_obj_align(chart, LV_ALIGN_CENTER, 0, 0);
     44     lv_obj_add_event_cb(chart, draw_event_cb, LV_EVENT_DRAW_PART_BEGIN, NULL);
     45     lv_obj_set_style_line_width(chart, 0, LV_PART_ITEMS);   /*Remove the lines*/
     46 
     47     lv_chart_set_type(chart, LV_CHART_TYPE_SCATTER);
     48 
     49     lv_chart_set_axis_tick(chart, LV_CHART_AXIS_PRIMARY_X, 5, 5, 5, 1, true, 30);
     50     lv_chart_set_axis_tick(chart, LV_CHART_AXIS_PRIMARY_Y, 10, 5, 6, 5, true, 50);
     51 
     52     lv_chart_set_range(chart, LV_CHART_AXIS_PRIMARY_X, 0, 200);
     53     lv_chart_set_range(chart, LV_CHART_AXIS_PRIMARY_Y, 0, 1000);
     54 
     55     lv_chart_set_point_count(chart, 50);
     56 
     57     lv_chart_series_t * ser = lv_chart_add_series(chart, lv_palette_main(LV_PALETTE_RED), LV_CHART_AXIS_PRIMARY_Y);
     58     uint32_t i;
     59     for(i = 0; i < 50; i++) {
     60         lv_chart_set_next_value2(chart, ser, lv_rand(0, 200), lv_rand(0, 1000));
     61     }
     62 
     63     lv_timer_create(add_data, 100, chart);
     64 }
     65 
     66 #endif