X-Git-Url: https://git.cworth.org/git?a=blobdiff_plain;f=acre.c;h=394b70035e9e5147516a7ec3ac3549c59edf7513;hb=f69ff8a99cf0d5884fd8d820513104c7953822b0;hp=672ba62bf776aaba82a4d966fc057a80ddcbe53d;hpb=ab7c095ffc2e9d6409fd2983b5462bb3d4609e60;p=acre diff --git a/acre.c b/acre.c index 672ba62..394b700 100644 --- a/acre.c +++ b/acre.c @@ -21,6 +21,7 @@ #include "xmalloc.h" #include +#include typedef struct _acre_data_point_2d { double x; @@ -35,14 +36,30 @@ struct _acre_data { 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. */ @@ -54,8 +71,14 @@ acre_create (void) 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; @@ -71,8 +94,8 @@ acre_destroy (acre_t *acre) 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]); @@ -93,17 +116,17 @@ acre_set_title (acre_t *acre, const char *title) 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 @@ -124,21 +147,213 @@ acre_add_data (acre_t *acre, acre_data_t *data) 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