#include "xmalloc.h"
#include <string.h>
+#include <math.h>
typedef struct _acre_data_point_2d {
double x;
unsigned int num_points;
};
+typedef struct _acre_axis {
+ char *label;
+ double min;
+ double max;
+} acre_axis_t;
+
struct _acre {
char *title;
- char *x_axis_label;
- char *y_axis_label;
+ acre_axis_t x_axis;
+ acre_axis_t y_axis;
acre_data_t **data;
unsigned int data_size;
unsigned int num_data;
+
+ /* Data for drawing. */
+ cairo_t *cr;
+
+ /* Total size including labels. */
+ int width;
+ int height;
+
+ /* Position and size of chart alone. */
+ PangoRectangle chart;
};
/* Create a new, empty plot. */
acre = xmalloc (sizeof (acre_t));
acre->title = NULL;
- acre->x_axis_label = NULL;
- acre->y_axis_label = NULL;
+
+ acre->x_axis.label = NULL;
+ acre->x_axis.min = 0.0;
+ acre->x_axis.max = 0.0;
+
+ acre->y_axis.label = NULL;
+ acre->y_axis.min = 0.0;
+ acre->y_axis.max = 0.0;
acre->data = NULL;
acre->data_size = 0;
unsigned int i;
free (acre->title);
- free (acre->x_axis_label);
- free (acre->y_axis_label);
+ free (acre->x_axis.label);
+ free (acre->y_axis.label);
for (i = 0; i < acre->num_data; i++)
acre_data_destroy (acre->data[i]);
void
acre_set_x_axis_label (acre_t *acre, const char *label)
{
- free (acre->x_axis_label);
+ free (acre->x_axis.label);
- acre->x_axis_label = strdup (label);
+ acre->x_axis.label = strdup (label);
}
void
acre_set_y_axis_label (acre_t *acre, const char *label)
{
- free (acre->y_axis_label);
+ free (acre->y_axis.label);
- acre->y_axis_label = strdup (label);
+ acre->y_axis.label = strdup (label);
}
/* Add a dataset to the plot. The plot assumes ownership of the
acre->num_data++;
}
+#define ACRE_FONT_FAMILY "sans"
+#define ACRE_FONT_SIZE 12
+#define ACRE_TITLE_FONT_SIZE 32
+#define ACRE_PAD (ACRE_FONT_SIZE)
+#define ACRE_TICK_SIZE 4
+
+static void
+_draw_title_and_labels (acre_t *acre)
+{
+ cairo_t *cr = acre->cr;
+ PangoFontDescription *acre_font, *title_font;
+ PangoLayout *title_layout, *x_axis_layout, *y_axis_layout;
+ int title_width, title_height;
+ int x_axis_width, x_axis_height;
+ int y_axis_width, y_axis_height;
+ PangoRectangle new_chart;
+
+ cairo_save (cr);
+
+ acre_font = pango_font_description_new ();
+ pango_font_description_set_family (acre_font, ACRE_FONT_FAMILY);
+ pango_font_description_set_absolute_size (acre_font,
+ ACRE_FONT_SIZE * PANGO_SCALE);
+
+ title_font = pango_font_description_new ();
+ pango_font_description_set_family (title_font, ACRE_FONT_FAMILY);
+ pango_font_description_set_absolute_size (title_font,
+ ACRE_TITLE_FONT_SIZE * PANGO_SCALE);
+
+ title_layout = pango_cairo_create_layout (cr);
+ pango_layout_set_font_description (title_layout, title_font);
+ pango_layout_set_text (title_layout, acre->title, -1);
+ pango_layout_set_alignment (title_layout, PANGO_ALIGN_CENTER);
+
+ x_axis_layout = pango_cairo_create_layout (cr);
+ pango_layout_set_font_description (x_axis_layout, acre_font);
+ pango_layout_set_text (x_axis_layout, acre->x_axis.label, -1);
+ pango_layout_set_alignment (x_axis_layout, PANGO_ALIGN_CENTER);
+
+ y_axis_layout = pango_cairo_create_layout (cr);
+ pango_layout_set_font_description (y_axis_layout, acre_font);
+ pango_layout_set_text (y_axis_layout, acre->y_axis.label, -1);
+ pango_layout_set_alignment (y_axis_layout, PANGO_ALIGN_CENTER);
+
+ /* Iterate with the layout of the title and axis labels until they
+ * are stable, (this requires iteration since we don't know what
+ * to set their widths to in advance due to the wrapping of the
+ * other elements). */
+ acre->chart.x = 0;
+ acre->chart.y = 0;
+ acre->chart.width = acre->width;
+ acre->chart.height = acre->height;
+ while (1) {
+ pango_layout_set_width (title_layout, acre->chart.width * PANGO_SCALE);
+ pango_layout_set_width (x_axis_layout, acre->chart.width * PANGO_SCALE);
+ pango_layout_set_width (y_axis_layout, acre->chart.height * PANGO_SCALE);
+
+ pango_layout_get_pixel_size (title_layout, &title_width, &title_height);
+ pango_layout_get_pixel_size (x_axis_layout, &x_axis_width, &x_axis_height);
+ pango_layout_get_pixel_size (y_axis_layout, &y_axis_width, &y_axis_height);
+
+ new_chart.x = ACRE_PAD + y_axis_height +
+ ACRE_PAD + ACRE_FONT_SIZE;
+ new_chart.width = acre->width - acre->chart.x - ACRE_PAD;
+
+ new_chart.y = ACRE_PAD + title_height + ACRE_PAD;
+ new_chart.height = acre->height - acre->chart.y - (ACRE_FONT_SIZE + ACRE_PAD + x_axis_height + ACRE_PAD);
+
+ if (new_chart.x == acre->chart.x &&
+ new_chart.y == acre->chart.y &&
+ new_chart.width == acre->chart.width &&
+ new_chart.height == acre->chart.height)
+ {
+ break;
+ }
+
+ acre->chart.x = new_chart.x;
+ acre->chart.y = new_chart.y;
+ acre->chart.width = new_chart.width;
+ acre->chart.height = new_chart.height;
+ }
+
+ cairo_set_source_rgb (cr, 0, 0, 0);
+
+ cairo_move_to (cr, acre->chart.x, ACRE_PAD);
+ pango_cairo_show_layout (cr, title_layout);
+
+ cairo_save (cr);
+ {
+ cairo_translate (cr, ACRE_PAD, acre->chart.y + acre->chart.height);
+ cairo_rotate (cr, - M_PI / 2.0);
+ cairo_move_to (cr, 0, 0);
+ pango_cairo_show_layout (cr, y_axis_layout);
+ }
+ cairo_restore (cr);
+
+ cairo_move_to (cr, acre->chart.x,
+ acre->chart.y + acre->chart.height +
+ ACRE_FONT_SIZE + ACRE_PAD);
+ pango_cairo_show_layout (cr, x_axis_layout);
+
+ cairo_restore (cr);
+}
+
+static void
+_compute_axis_ranges (acre_t *acre)
+{
+ unsigned int d, i;
+ acre_data_t *data;
+
+ for (d = 0; d < acre->num_data; d++) {
+ data = acre->data[d];
+ for (i = 0; i < data->num_points; i++) {
+ if (data->points[i].x < acre->x_axis.min)
+ acre->x_axis.min = data->points[i].x;
+ if (data->points[i].x > acre->x_axis.max)
+ acre->x_axis.max = data->points[i].x;
+
+ if (data->points[i].y < acre->y_axis.min)
+ acre->y_axis.min = data->points[i].y;
+ if (data->points[i].y > acre->y_axis.max)
+ acre->y_axis.max = data->points[i].y;
+ }
+ }
+}
+
+static void
+_draw_data (acre_t *acre)
+{
+ cairo_t *cr = acre->cr;
+ unsigned int d, i;
+ acre_data_t *data;
+
+ cairo_save (cr);
+
+ cairo_set_source_rgb (cr, 0, 0, 0);
+
+ cairo_translate (cr,
+ acre->chart.x + 0.5,
+ acre->chart.y + acre->chart.height - 0.5);
+ cairo_scale (cr,
+ acre->chart.width / (acre->x_axis.max - acre->x_axis.min),
+ - acre->chart.height /(acre->y_axis.max - acre->y_axis.min));
+ cairo_translate (cr, -acre->x_axis.min, -acre->y_axis.min);
+
+ for (d = 0; d < acre->num_data; d++) {
+ data = acre->data[d];
+ cairo_new_path (cr);
+ for (i = 0; i < data->num_points; i++) {
+ cairo_line_to (cr,
+ data->points[i].x,
+ data->points[i].y);
+ }
+ cairo_save (cr);
+ {
+ cairo_identity_matrix (cr);
+ cairo_set_line_width (cr, 1.0);
+ cairo_stroke (cr);
+ }
+ cairo_restore (cr);
+ }
+
+ cairo_restore (cr);
+}
+
+static void
+_draw_frame_and_ticks (acre_t *acre)
+{
+ cairo_t *cr = acre->cr;
+
+ cairo_save (cr);
+
+ cairo_rectangle (cr,
+ acre->chart.x - 0.5, acre->chart.y - 0.5,
+ acre->chart.width + 1.0, acre->chart.height + 1.0);
+ cairo_set_line_width (cr, 1.0);
+ cairo_set_source_rgb (cr, 0, 0, 0);
+ cairo_stroke (cr);
+
+ cairo_restore (cr);
+}
+
/* Draw the plot to the given cairo context within a user-space
* rectangle from (0, 0) to (width, height). This size includes all
* space for extra-plot elements (such as the title, the axis labels,
* etc.)
*/
void
-acre_draw (acre_t *acre, cairo_t *cr, double width, double height)
+acre_draw (acre_t *acre, cairo_t *cr, int width, int height)
{
- cairo_save (cr);
+ acre->cr = cr;
+ acre->width = width;
+ acre->height = height;
- cairo_rectangle (cr, 0, 0, width, height);
+ cairo_save (cr);
- cairo_set_source_rgb (cr, 1, 0, 1);
+ cairo_set_source_rgb (cr, 1, 1, 1);
cairo_paint (cr);
+
+ _draw_title_and_labels (acre);
+
+ _compute_axis_ranges (acre);
+
+ _draw_data (acre);
+
+ _draw_frame_and_ticks (acre);
}
/* Create a new dataset---a collection of (x, y) datapoints. A single
projects / acre / blobdiff