X-Git-Url: https://git.cworth.org/git?a=blobdiff_plain;f=acre.c;h=bda8e81996c3e72cdfad5e634a7ddf132ee0902e;hb=b58094819fb79d0d7e30ff57ddfdb7c3926302c5;hp=12be71d249952421f0fb17caa956e3cd74377a0f;hpb=af6a6a5cafbbbbb1d5e1cffcab4c5903853d9758;p=acre diff --git a/acre.c b/acre.c index 12be71d..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); } @@ -166,6 +185,8 @@ acre_add_data (acre_t *acre, acre_data_t *data) #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) @@ -496,22 +517,84 @@ _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) { 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); @@ -520,11 +603,11 @@ _draw_data (acre_t *acre) _set_transform_to_data_space (acre); for (d = 0; d < acre->num_data; d++) { - int color = d % NUM_COLORS; + int color = d % acre->num_colors; cairo_set_source_rgb (cr, - colors[color].r, - colors[color].g, - colors[color].b); + 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++) { @@ -628,6 +711,64 @@ _draw_ticks (acre_t *acre, 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) { @@ -671,6 +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); @@ -683,6 +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); }