#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_SIZE 6
+#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
/* For a given axis range, compute a step size (in data space) to
* generate a suitable number of ticks (5 or so). */
static double
-_step_for_range (double range)
+_step_for_range (double range, int *minor_divisions)
{
double step, scale_factor;
* 10). The threshold values between these are computed
* logarithmically. */
if (step < 3.535533905932738) {
- if (step < 1.58113883008419)
+ if (step < 1.58113883008419) {
step = 1.0;
- else
+ *minor_divisions = 4;
+ } else {
step = 2.5;
+ *minor_divisions = 5;
+ }
} else {
- if (step < 7.071067811865475)
+ if (step < 7.071067811865475) {
step = 5.0;
- else
+ *minor_divisions = 5;
+ } else {
step = 10.0;
+ *minor_divisions = 4;
+ }
}
/* Un-normalize and we now have the data value that we want to
* 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);
- pixel_step = step * pixel_size / range;
+ step = _step_for_range (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_t *cr = acre->cr;
unsigned int d, i;
acre_data_t *data;
+#define NUM_COLORS 3
+ struct {
+ double r;
+ double g;
+ double b;
+ } colors [NUM_COLORS] = {
+ {1, 0, 0},
+ {0, 1, 0},
+ {0, 0, 1}
+ };
cairo_save (cr);
_set_transform_to_data_space (acre);
for (d = 0; d < acre->num_data; d++) {
+ int color = d % NUM_COLORS;
+ cairo_set_source_rgb (cr,
+ colors[color].r,
+ colors[color].g,
+ colors[color].b);
data = acre->data[d];
cairo_new_path (cr);
for (i = 0; i < data->num_points; i++) {
acre_ticks_t ticks)
{
cairo_t *cr = acre->cr;
- double i, step;
+ double t, step, sub_step;
+ int minor_divisions;
cairo_save (cr);
_set_transform_to_data_space (acre);
- step = _step_for_range (axis_max - axis_min);
- i = (floor (axis_min / step) + 1) * step;
+ step = _step_for_range (axis_max - axis_min, &minor_divisions);
+ sub_step = step / minor_divisions;
- while (i <= axis_max) {
- if (ticks == ACRE_TICKS_X)
- cairo_move_to (cr, i, acre->y_axis.min);
+ for (t = (floor (axis_min / sub_step) + 1) * sub_step;
+ t <= axis_max;
+ t += sub_step)
+ {
+ int tick_size;
+ if (fabs((t / step) - round (t / step)) < 0.5 * (sub_step / step))
+ tick_size = ACRE_TICK_MAJOR_SIZE;
else
- cairo_move_to (cr, acre->x_axis.min, i);
+ tick_size = ACRE_TICK_MINOR_SIZE;
/* tick */
cairo_save (cr);
{
+ if (ticks == ACRE_TICKS_X)
+ cairo_move_to (cr, t, acre->y_axis.min);
+ else
+ cairo_move_to (cr, acre->x_axis.min, t);
+
cairo_identity_matrix (cr);
+
if (ticks == ACRE_TICKS_X) {
cairo_rel_line_to (cr, 0, 0.5);
- cairo_rel_line_to (cr, 0, -ACRE_TICK_SIZE-0.5);
+ cairo_rel_line_to (cr, 0, -tick_size - 0.5);
} else {
cairo_rel_line_to (cr, -0.5, 0);
- cairo_rel_line_to (cr, ACRE_TICK_SIZE+0.5, 0);
+ cairo_rel_line_to (cr, tick_size + 0.5, 0);
}
+
cairo_set_line_width (cr, 1.0);
cairo_stroke (cr);
}
cairo_restore (cr);
/* label */
- cairo_save (cr);
+ if (tick_size == ACRE_TICK_MAJOR_SIZE)
{
PangoLayout *layout;
int width, height;
- layout = _create_layout_printf (acre, "%g", i);
+ cairo_save (cr);
+
+ layout = _create_layout_printf (acre, "%g", t);
if (ticks == ACRE_TICKS_X)
- cairo_move_to (cr, i, acre->y_axis.min);
+ cairo_move_to (cr, t, acre->y_axis.min);
else
- cairo_move_to (cr, acre->x_axis.min, i);
+ cairo_move_to (cr, acre->x_axis.min, t);
cairo_identity_matrix (cr);
pango_layout_get_pixel_size (layout, &width, &height);
-height/2);
_show_layout (cr, layout);
- }
- cairo_restore (cr);
- i += step;
+ cairo_restore (cr);
+ }
}
cairo_restore (cr);
projects / acre / blobdiff