double max;
} acre_axis_t;
+typedef struct _acre_color {
+ double red;
+ double green;
+ double blue;
+} acre_color_t;
+
struct _acre {
char *title;
acre_axis_t x_axis;
/* Data for drawing. */
cairo_t *cr;
PangoFontDescription *font;
+ acre_color_t *colors;
+ int colors_size;
+ int num_colors;
/* Total size including labels. */
int width;
acre->data_size = 0;
acre->num_data = 0;
+ acre->cr = NULL;
+ acre->font = NULL;
+ acre->colors = NULL;
+ acre->num_colors = 0;
+
+ acre->width = 0;
+ acre->height = 0;
+
acre->chart.x = 0;
acre->chart.y = 0;
acre->chart.width = 0;
free (acre->data);
+ free (acre->colors);
+
free (acre);
}
#define ACRE_FONT_FAMILY "sans"
#define ACRE_FONT_SIZE 12
-#define ACRE_TITLE_FONT_SIZE 32
+#define ACRE_TITLE_FONT_SIZE 20
#define ACRE_PAD (ACRE_FONT_SIZE)
#define ACRE_TICK_MAJOR_SIZE 6
#define ACRE_TICK_MINOR_SIZE 3
#define ACRE_X_TICK_VALUE_PAD 2
#define ACRE_Y_TICK_VALUE_PAD 4
+#define ACRE_LEGEND_PAD 4
+#define ACRE_LEGEND_LINE_SIZE 10
static PangoLayout *
_create_layout (acre_t *acre, const char *text)
* nice-looking pixel-snapped ticks we want to expand the range
* slightly. */
static void
-_expand_range_for_width (double *axis_min, double *axis_max, int pixel_size)
+_expand_range_for_width (double *axis_min, double *axis_max, int pixel_range)
{
- double range, new_range, step, pixel_step;
+ double range, new_range, step, step_minor, pixel_step;
int minor_divisions;
range = *axis_max - *axis_min;
step = _step_for_range (range, &minor_divisions);
- pixel_step = step * pixel_size / range / minor_divisions;
+ step_minor = step / minor_divisions;
+
+ pixel_step = step_minor * (pixel_range / range);
/* We expand the range by the ratio of the pixel step to the floor
* of the pixel_step.
}
}
- /* Next, increase the axis ranges just enough so that the step
+ /* Next, we want to ensure that the data never collides with the
+ * ticks. So we expand each axis on its minimum side as needed. */
+ cairo_save (cr);
+ {
+ double x, y;
+
+ _set_transform_to_data_space (acre);
+
+ x = ACRE_TICK_MAJOR_SIZE + 2.0;
+ y = ACRE_TICK_MAJOR_SIZE + 2.0;
+ cairo_device_to_user_distance (cr, &x, &y);
+
+ acre->x_axis.min -= x;
+ acre->y_axis.min += y;
+ }
+ cairo_restore (cr);
+
+ /* Then, increase the axis ranges just enough so that the step
* sizes for the ticks will be integers.
*/
_expand_range_for_width (&acre->x_axis.min,
cairo_restore (cr);
}
+static void
+_acre_color_from_hsv (acre_color_t *color,
+ double hue,
+ double saturation,
+ double value)
+{
+ double f, p, q, t;
+ int hmod6;
+
+ hmod6 = (int) floor (hue / 60) % 6;
+ f = hue / 60 - floor (hue / 60);
+ p = value * (1 - saturation);
+ q = value * (1 - f * saturation);
+ t = value * (1 - (1 - f) * saturation);
+
+ switch (hmod6) {
+ case 0:
+ color->red = value;
+ color->green = t;
+ color->blue = p;
+ break;
+ case 1:
+ color->red = q;
+ color->green = value;
+ color->blue = p;
+ break;
+ case 2:
+ color->red = p;
+ color->green = value;
+ color->blue = t;
+ break;
+ case 3:
+ color->red = p;
+ color->green = q;
+ color->blue = value;
+ break;
+ case 4:
+ color->red = t;
+ color->green = p;
+ color->blue = value;
+ break;
+ case 5:
+ color->red = value;
+ color->green = p;
+ color->blue = q;
+ break;
+ }
+}
+
+static void
+_choose_colors (acre_t *acre)
+{
+ double hue, saturation, value;
+ int i;
+
+ acre->num_colors = acre->num_data;
+
+ if (acre->num_colors > acre->colors_size) {
+ acre->colors_size = acre->num_colors;
+ acre->colors = xrealloc (acre->colors,
+ acre->colors_size * sizeof (acre_color_t));
+ }
+
+ saturation = 1.0;
+ value = 0.7;
+ for (i = 0; i < acre->num_colors; i++) {
+ hue = 360 * (double) i / acre->num_colors;
+ _acre_color_from_hsv (&acre->colors[i],
+ hue, saturation, value);
+ }
+}
+
static void
_draw_data (acre_t *acre)
{
_set_transform_to_data_space (acre);
for (d = 0; d < acre->num_data; d++) {
+ int color = d % acre->num_colors;
+ cairo_set_source_rgb (cr,
+ acre->colors[color].red,
+ acre->colors[color].green,
+ acre->colors[color].blue);
data = acre->data[d];
cairo_new_path (cr);
for (i = 0; i < data->num_points; i++) {
t += sub_step)
{
int tick_size;
- if (fabs((t / step) - (int) (t / step)) < 0.5 * (sub_step / step))
+ if (fabs((t / step) - round (t / step)) < 0.5 * (sub_step / step))
tick_size = ACRE_TICK_MAJOR_SIZE;
else
tick_size = ACRE_TICK_MINOR_SIZE;
cairo_restore (cr);
}
+static void
+_draw_legend (acre_t *acre)
+{
+ PangoLayout *layout;
+ int label_width, max_label_width = 0;
+ int width, height;
+ unsigned int i;
+ cairo_t *cr = acre->cr;
+
+ cairo_save (cr);
+
+ for (i = 0; i < acre->num_data; i++) {
+ layout = _create_layout (acre, acre->data[i]->name);
+ pango_layout_get_pixel_size (layout, &label_width, NULL);
+ _destroy_layout (layout);
+ if (label_width > max_label_width)
+ max_label_width = label_width;
+ }
+
+ width = ACRE_LEGEND_PAD + ACRE_LEGEND_LINE_SIZE + ACRE_LEGEND_PAD +
+ max_label_width + ACRE_LEGEND_PAD;
+ height = ACRE_LEGEND_PAD +
+ acre->num_data * (ACRE_FONT_SIZE + ACRE_LEGEND_PAD);
+
+ cairo_translate (cr, acre->chart.x, acre->chart.y);
+
+ cairo_translate (cr,
+ acre->chart.width - ACRE_LEGEND_PAD - width,
+ ACRE_LEGEND_PAD);
+
+ cairo_rectangle (cr, -0.5, -0.5, width + 1.0, height + 1.0);
+ cairo_set_source_rgb (cr, 0, 0, 0);
+ cairo_set_line_width (cr, 1.0);
+ cairo_stroke (cr);
+
+ cairo_translate (cr, ACRE_LEGEND_PAD, ACRE_LEGEND_PAD);
+
+ for (i = 0; i < acre->num_data; i++) {
+ cairo_rectangle (cr,
+ 0, ACRE_LEGEND_LINE_SIZE / 2,
+ ACRE_LEGEND_LINE_SIZE, ACRE_LEGEND_LINE_SIZE / 2);
+ cairo_set_source_rgb (cr,
+ acre->colors[i % acre->num_colors].red,
+ acre->colors[i % acre->num_colors].green,
+ acre->colors[i % acre->num_colors].blue);
+ cairo_fill (cr);
+
+ layout = _create_layout (acre, acre->data[i]->name);
+ cairo_move_to (cr, ACRE_LEGEND_LINE_SIZE + ACRE_LEGEND_PAD, 0);
+ cairo_set_source_rgb (cr, 0, 0, 0);
+ _show_layout (cr, layout);
+
+ cairo_translate (cr, 0, ACRE_LEGEND_PAD + ACRE_FONT_SIZE);
+ }
+
+ cairo_restore (cr);
+}
+
static void
_draw_frame_and_ticks (acre_t *acre)
{
cairo_set_source_rgb (cr, 1, 1, 1);
+ _choose_colors (acre);
+
/* We compute the axis ranges before doing label layout so that we
* can account for the width of the y-axis value labels. */
_compute_axis_ranges (acre);
_draw_data (acre);
+ if (acre->num_data > 1)
+ _draw_legend (acre);
+
_draw_frame_and_ticks (acre);
}
projects / acre / blobdiff