X-Git-Url: https://git.cworth.org/git?a=blobdiff_plain;f=acre.c;h=bda8e81996c3e72cdfad5e634a7ddf132ee0902e;hb=b58094819fb79d0d7e30ff57ddfdb7c3926302c5;hp=a01dbe5c2f1275c0c4f77b049844c8220b2c69e8;hpb=5897f1f7f868e2fdfa51fc8e3bb9e02d49171b2b;p=acre diff --git a/acre.c b/acre.c index a01dbe5..bda8e81 100644 --- a/acre.c +++ b/acre.c @@ -47,6 +47,12 @@ typedef struct _acre_axis { 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; @@ -59,6 +65,9 @@ struct _acre { /* Data for drawing. */ cairo_t *cr; PangoFontDescription *font; + acre_color_t *colors; + int colors_size; + int num_colors; /* Total size including labels. */ int width; @@ -90,6 +99,14 @@ acre_create (void) 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; @@ -113,6 +130,8 @@ acre_destroy (acre_t *acre) free (acre->data); + free (acre->colors); + free (acre); } @@ -160,11 +179,14 @@ acre_add_data (acre_t *acre, acre_data_t *data) #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 +#define ACRE_LEGEND_PAD 4 +#define ACRE_LEGEND_LINE_SIZE 10 static PangoLayout * _create_layout (acre_t *acre, const char *text) @@ -333,7 +355,7 @@ _draw_title_and_labels (acre_t *acre) /* 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; @@ -349,15 +371,21 @@ _step_for_range (double range) * 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 @@ -370,14 +398,17 @@ _step_for_range (double range) * 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. @@ -435,7 +466,24 @@ _compute_axis_ranges (acre_t *acre) } } - /* 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, @@ -469,6 +517,78 @@ _compute_axis_ranges (acre_t *acre) 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) { @@ -483,6 +603,11 @@ _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++) { @@ -510,49 +635,63 @@ _draw_ticks (acre_t *acre, 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); @@ -564,10 +703,67 @@ _draw_ticks (acre_t *acre, -height/2); _show_layout (cr, layout); + + cairo_restore (cr); } - cairo_restore (cr); + } + + 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; - i += step; + 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); @@ -616,6 +812,8 @@ acre_draw (acre_t *acre, cairo_t *cr, int width, int height) 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); @@ -628,6 +826,9 @@ acre_draw (acre_t *acre, cairo_t *cr, int width, int height) _draw_data (acre); + if (acre->num_data > 1) + _draw_legend (acre); + _draw_frame_and_ticks (acre); }