return screen_p;
}
+static void draw_data(BVChartPrivate *priv, cairo_t *cr,
+ GtkAllocation *allocation) {
+ cairo_set_source_rgb(cr, 0.0, 0.0, 1.0);
+ float gap_threshold = 3.0;
+ float prevx = 0.0;
+ for (guint i = 0; i < priv->points->len; i++) {
+ struct BVChartPoint *p =
+ &g_array_index(priv->points, struct BVChartPoint, i);
+ gboolean is_gap = p->x - prevx > gap_threshold;
+ cairo_draw_func f = is_gap ? cairo_move_to : cairo_line_to;
+ struct ScreenPoint screen_p = to_screen(priv, allocation, p);
+ f(cr, screen_p.x, screen_p.y);
+ prevx = p->x;
+ }
+ cairo_stroke(cr);
+}
+
+static void draw_axis(BVChartPrivate *priv, cairo_t *cr,
+ GtkAllocation *allocation) {
+ if (priv->miny < 0.0 && priv->maxy > 0.0) {
+ cairo_set_source_rgb(cr, 0.0, 0.0, 0.0);
+ struct BVChartPoint p = {.x = priv->minx, .y = 0.0};
+ struct ScreenPoint screen_p = to_screen(priv, allocation, &p);
+ cairo_move_to(cr, screen_p.x, screen_p.y);
+ p.x = priv->maxx;
+ screen_p = to_screen(priv, allocation, &p);
+ cairo_line_to(cr, screen_p.x, screen_p.y);
+ cairo_stroke(cr);
+ }
+}
+
static gboolean bv_chart_draw(GtkWidget *widget, cairo_t *cr) {
BVChart *chart = BV_CHART(widget);
BVChartPrivate *priv = bv_chart_get_instance_private(chart);
GtkAllocation allocation;
gtk_widget_get_allocation(widget, &allocation);
- cairo_set_source_rgb(cr, 0.0, 0.0, 1.0);
- float gap_threshold = 3.0;
- float prevx = 0.0;
- for (guint i = 0; i < priv->points->len; i++) {
- struct BVChartPoint *p =
- &g_array_index(priv->points, struct BVChartPoint, i);
- gboolean is_gap = p->x - prevx > gap_threshold;
- cairo_draw_func f = is_gap ? cairo_move_to : cairo_line_to;
- struct ScreenPoint screen_p = to_screen(priv, &allocation, p);
- f(cr, screen_p.x, screen_p.y);
- prevx = p->x;
- }
- cairo_stroke(cr);
+ draw_axis(priv, cr, &allocation);
+ draw_data(priv, cr, &allocation);
return TRUE;
}