X-Git-Url: https://git.cworth.org/git?p=acre;a=blobdiff_plain;f=acre.c;h=9f6f26ebaab1f854cd8cd392c92d19fa64a92e6c;hp=5177419ae1b8c7b203851a4878e3d6201101840b;hb=HEAD;hpb=ffb47f290a9cf9cd9b36ba6ab0905b8f7be8bc6a

diff --git a/acre.c b/acre.c
index 5177419..9f6f26e 100644
--- a/acre.c
+++ b/acre.c
@@ -37,14 +37,31 @@ typedef struct _acre_data_point_2d {
 } acre_data_point_2d_t;
 
 struct _acre_data {
+    /* The name of this data set. */
     char *name;
 
+    /* The style for rendering (line, bar, etc.) */
+    acre_style_t style;
+
+    /* Minimum and mximum extents of data. */
     acre_data_point_2d_t min;
     acre_data_point_2d_t max;
 
+    /* The data itself. */
     acre_data_point_2d_t *points;
     unsigned int points_size;
     unsigned int num_points;
+
+    /* The names of data points (if any).
+     *
+     * This array is indexed with the same index as the 'points' array
+     * to provide names for points. It is legal for this array to be
+     * NULL or smaller than 'points', (in which case, the
+     * corresponding points simply have no names).
+     */
+    char **names;
+    unsigned int names_size;
+    unsigned int num_names;
 };
 
 typedef struct _acre_axis {
@@ -134,6 +151,7 @@ acre_create (void)
     acre->font = NULL;
     acre->colors = NULL;
     acre->num_colors = 0;
+    acre->colors_size = 0;
 
     acre->width = 0;
     acre->height = 0;
@@ -310,6 +328,20 @@ acre_add_data (acre_t *acre, acre_data_t *data)
 
     acre->data[acre->num_data] = data;
 
+    /* For timeline datasets, the X and Y ranges need to be
+     * adjusted. The desired X range is the min/max of the X and Y
+     * ranges, and the desired Y range has a size of 1.0 (centered
+     * around the dataset's index) */
+    if (data->style == ACRE_STYLE_TIMELINE) {
+	if (data->min.y < data->min.x)
+	    data->min.x = data->min.y;
+	if (data->max.y > data->max.x)
+	    data->max.x = data->max.y;
+
+	data->min.y = acre->num_data -0.5;
+	data->max.y = acre->num_data + 0.5;
+    }
+
     if (acre->num_data == 0) {
 	acre->x_axis.data_min = data->min.x;
 	acre->y_axis.data_min = data->min.y;
@@ -350,11 +382,16 @@ _create_layout (acre_t *acre, const char *text)
     if (text == NULL)
 	    text = "";
 
+    cairo_save (acre->cr);
+    cairo_identity_matrix (acre->cr);
+
     layout = pango_cairo_create_layout (acre->cr);
     pango_layout_set_font_description (layout, acre->font);
     pango_layout_set_text (layout, text, -1);
     pango_layout_set_alignment (layout, PANGO_ALIGN_CENTER);
 
+    cairo_restore (acre->cr);
+
     return layout;
 }
 
@@ -435,6 +472,7 @@ _draw_title_and_labels (acre_t *acre)
 
     title_layout = _create_layout (acre, acre->title);
     pango_layout_set_font_description (title_layout, title_font);
+    pango_font_description_free (title_font);
 
     x_axis_layout = _create_layout (acre, acre->x_axis.label);
     y_axis_layout = _create_layout (acre, acre->y_axis.label);
@@ -645,6 +683,11 @@ _find_y_range_given_x_range (acre_t *acre,
 
     for (d = 0; d < acre->num_data; d++) {
 	data = acre->data[d];
+
+	/* Never mess with the Y range for timeline data. */
+	if (data->style == ACRE_STYLE_TIMELINE)
+	    continue;
+
 	for (i = 0; i < data->num_points; i++) {
 	    if (data->points[i].x >= x_min &&
 		data->points[i].x <= x_max)
@@ -779,11 +822,149 @@ _choose_colors (acre_t *acre)
     cmsCloseProfile (srgb_profile);
 }
 
+/* Draw the given dataset as a line. */
+static void
+_draw_data_line (acre_t *acre, acre_data_t *data)
+{
+    unsigned i;
+    cairo_t *cr = acre->cr;
+
+    cairo_save (cr);
+
+    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_identity_matrix (cr);
+    cairo_set_line_width (cr, 1.0);
+    cairo_stroke (cr);
+
+    cairo_restore (cr);
+}
+
+#define BARS_WIDTH 0.8
+
+/* Draw the given dataset as bars. */
+static void
+_draw_data_bars (acre_t *acre, acre_data_t *data)
+{
+    unsigned i;
+    cairo_t *cr = acre->cr;
+
+    cairo_save (cr);
+
+    cairo_new_path (cr);
+
+    for (i = 0; i < data->num_points; i++) {
+	cairo_rectangle (cr,
+			 data->points[i].x - BARS_WIDTH / 2.0, 0.0,
+			 BARS_WIDTH, data->points[i].y);
+    }
+
+    cairo_identity_matrix (cr);
+    cairo_set_line_width (cr, 1.0);
+    cairo_stroke (cr);
+
+    cairo_restore (cr);
+}
+
+/* Draw the given dataset as bars if there is room for that.
+ *
+ * Or, if the bars would run into each other, use a line instead.
+ */
+static void
+_draw_data_bars_or_line (acre_t *acre, acre_data_t *data)
+{
+    cairo_t *cr = acre->cr;
+    double ignored, width;
+
+    /* Check device-space width available for inter-bar padding. */
+    width = 1.0 - BARS_WIDTH;
+    ignored = 0.0;
+    cairo_user_to_device_distance (cr, &width, &ignored);
+
+    /* If padding is less than two pixels, draw with a line instead. */
+    if (width < 2.0)
+	_draw_data_line (acre, data);
+    else
+	_draw_data_bars (acre, data);
+}
+
+#define TIMELINE_BAR_HEIGHT 0.6
+
+/* Draw the given dataset as a timeline. Each (X,Y) point (potentially
+ * with a name) specifies the (start,stop) of a single timeline bar.
+ *
+ * Each independent timeline dataset in the chart is given its own
+ * vertical position, as specified by 'y_position'.
+ */
+static void
+_draw_data_timeline (acre_t *acre, acre_data_t *data, int y_position)
+{
+    unsigned i;
+    cairo_t *cr = acre->cr;
+    PangoLayout *timeline_label_layout;
+    double ignored, label_offset;
+    int labels_within_bar;
+
+    cairo_save (cr);
+
+    timeline_label_layout = _create_layout (acre, "Timeline");
+    pango_layout_set_font_description (timeline_label_layout, acre->font);
+
+    ignored = 0.0;
+    label_offset = ACRE_FONT_SIZE;
+    cairo_device_to_user_distance (cr, &ignored, &label_offset);
+
+    labels_within_bar = TIMELINE_BAR_HEIGHT / fabs (label_offset);
+
+    for (i = 0; i < data->num_points; i++) {
+	cairo_rectangle (cr,
+			 data->points[i].x,
+			 y_position - TIMELINE_BAR_HEIGHT / 2.0,
+			 data->points[i].y - data->points[i].x,
+			 TIMELINE_BAR_HEIGHT);
+
+	cairo_save (cr);
+	cairo_identity_matrix (cr);
+	cairo_set_line_width (cr, 1.0);
+	cairo_stroke_preserve (cr);
+	cairo_restore (cr);
+
+	cairo_new_path (cr);
+
+	if (i <= data->num_names && data->names[i]) {
+	    cairo_save (cr);
+
+	    cairo_move_to (cr, data->points[i].x,
+			   y_position + TIMELINE_BAR_HEIGHT / 2.0 +
+			   (i % labels_within_bar) * label_offset);
+	    pango_layout_set_text (timeline_label_layout, data->names[i], -1);
+	    cairo_identity_matrix (cr);
+	    pango_cairo_show_layout (cr, timeline_label_layout);
+
+	    cairo_restore (cr);
+	} else {
+	    cairo_new_path (cr);
+	}
+
+    }
+
+    _destroy_layout (timeline_label_layout);
+
+    cairo_restore (cr);
+}
+
+/* Draw all the datasets of the chart. */
 static void
 _draw_data (acre_t *acre)
 {
     cairo_t *cr = acre->cr;
-    unsigned int d, i;
+    unsigned int i;
     acre_data_t *data;
 
     cairo_save (cr);
@@ -797,28 +978,29 @@ _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;
+    for (i = 0; i < acre->num_data; i++) {
+	int color = i % 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);
+	data = acre->data[i];
 
-	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);
+	switch (data->style) {
+	case ACRE_STYLE_LINE:
+	    _draw_data_line (acre, data);
+	    break;
+	case ACRE_STYLE_BARS:
+	    _draw_data_bars (acre, data);
+	    break;
+	case ACRE_STYLE_BARS_OR_LINE:
+	    _draw_data_bars_or_line (acre, data);
+	    break;
+	case ACRE_STYLE_TIMELINE:
+	    /* Position the timeline bars top-down */
+	    _draw_data_timeline (acre, data, acre->num_data - 1 - i);
+	    break;
 	}
-	cairo_restore (cr);
     }
 
     cairo_restore (cr);
@@ -880,10 +1062,14 @@ _draw_ticks (acre_t *acre,
 	{
 	    PangoLayout *layout;
 	    int width, height;
+	    double label_value;
 
 	    cairo_save (cr);
 
-	    layout = _create_layout_printf (acre, "%g", t);
+	    label_value = t;
+	    if (fabs (label_value) < (sub_step / 1000.))
+		label_value = 0.0;
+	    layout = _create_layout_printf (acre, "%g", label_value);
 
 	    if (ticks == ACRE_TICKS_X)
 		cairo_move_to (cr, t, acre->y_axis.view_min);
@@ -1040,6 +1226,8 @@ acre_data_create (void)
 
     data->name = NULL;
 
+    data->style = ACRE_STYLE_LINE;
+
     data->points = NULL;
     data->points_size = 0;
     data->num_points = 0;
@@ -1052,11 +1240,27 @@ acre_data_create (void)
 void
 acre_data_destroy (acre_data_t *data)
 {
+    unsigned i;
+
+    for (i = 0; i < data->num_names; i++) {
+	if (data->names[i])
+	    free (data->names[i]);
+    }
+    free (data->names);
+
+    free (data->name);
+
     free (data->points);
 
     free (data);
 }
 
+void
+acre_data_set_style (acre_data_t *data, acre_style_t style)
+{
+    data->style = style;
+}
+
 /* Set the label for this dataset (to appear in the plot's key). */
 void
 acre_data_set_name (acre_data_t *data, const char *name)
@@ -1102,3 +1306,27 @@ acre_data_add_point_2d (acre_data_t *data, double x, double y)
 
     data->num_points++;
 }
+
+/* Add a datapoint with a name to the given dataset. */
+void
+acre_data_add_point_2d_named (acre_data_t *data, double x, double y, const char *name)
+{
+    unsigned i;
+
+    acre_data_add_point_2d (data, x, y);
+
+    if (data->names_size < data->points_size) {
+	data->names_size = data->points_size;
+	data->names = xrealloc_ab (data->names,
+				   data->names_size,
+				   sizeof (char *));
+    }
+
+    /* Initialize any newly-created holes in the array to NULL. */
+    for (i = data->num_names; i < data->num_points - 1; i++)
+	data->names[i] = NULL;
+
+    data->num_names = data->num_points;
+
+    data->names[data->num_names - 1] = xstrdup (name);
+}