git.scottworley.com Git - batteryviewer/blob - chart.c

   1 /*
   2  * h/t https://ptomato.name/advanced-gtk-techniques/html/custom-container.html
   3  * for examples of how to make GTK widgets
   4  */
   5
   6 #include "chart.h"
   7 #include <float.h>
   8 #include <gtk/gtk.h>
   9
  10 #define BV_CHART_PRIVATE(obj)                                                  \
  11   (G_TYPE_INSTANCE_GET_PRIVATE((obj), BV_CHART_TYPE, BVChartPrivate))
  12
  13 typedef struct _BVChartPrivate BVChartPrivate;
  14
  15 struct _BVChartPrivate {
  16   GArray *points;
  17   float minx, miny, maxx, maxy;
  18 };
  19
  20 struct BVChartPoint {
  21   float x, y;
  22 };
  23
  24 G_DEFINE_TYPE_WITH_CODE(BVChart, bv_chart, GTK_TYPE_DRAWING_AREA,
  25                         G_ADD_PRIVATE(BVChart))
  26
  27 static void bv_chart_class_init(BVChartClass *klass __attribute__((unused))) {}
  28
  29 static void bv_chart_init(BVChart *chart) {
  30   gtk_widget_set_has_window(GTK_WIDGET(chart), FALSE);
  31   BVChartPrivate *priv = bv_chart_get_instance_private(chart);
  32   gboolean zero_terminated = FALSE;
  33   gboolean clear_ = FALSE;
  34   priv->points =
  35       g_array_new(zero_terminated, clear_, sizeof(struct BVChartPoint));
  36   priv->minx = FLT_MAX;
  37   priv->miny = FLT_MAX;
  38   priv->maxx = FLT_MIN;
  39   priv->maxy = FLT_MIN;
  40 }
  41
  42 GtkWidget *bv_chart_new() {
  43   return GTK_WIDGET(g_object_new(bv_chart_get_type(), NULL));
  44 }
  45
  46 void bv_chart_add_point(BVChart *chart, float x, float y) {
  47   BVChartPrivate *priv = bv_chart_get_instance_private(chart);
  48   if (x < priv->minx)
  49     priv->minx = x;
  50   if (y < priv->miny)
  51     priv->miny = y;
  52   if (x > priv->maxx)
  53     priv->maxx = x;
  54   if (y > priv->maxy)
  55     priv->maxy = y;
  56   struct BVChartPoint p = {.x = x, .y = y};
  57   g_array_append_val(priv->points, p);
  58 }