Add option to display labels

include/slurp.h

@@ -12,6 +12,14 @@
 
 #define TOUCH_ID_EMPTY -1
 
+enum slurp_label_anchor {
+	ANCHOR_NONE = 0,
+	ANCHOR_TOP = 1,
+	ANCHOR_BOTTOM = 2,
+	ANCHOR_LEFT = 4,
+	ANCHOR_RIGHT = 8,
+};
+
 struct slurp_box {
 	int32_t x, y;
 	int32_t width, height;
@@ -48,6 +56,8 @@ struct slurp_state {
 		uint32_t border;
 		uint32_t selection;
 		uint32_t choice;
+		uint32_t label_text;
+		uint32_t label_background;
 	} colors;
 
 	const char *font_family;
@@ -60,6 +70,7 @@ struct slurp_state {
 	struct wl_list boxes; // slurp_box::link
 	bool fixed_aspect_ratio;
 	double aspect_ratio;  // h / w
+	enum slurp_label_anchor label_anchor;
 
 	struct slurp_box result;
 };

main.c

@@ -17,6 +17,8 @@
 #define BG_COLOR 0xFFFFFF40
 #define BORDER_COLOR 0x000000FF
 #define SELECTION_COLOR 0x00000000
+#define LABEL_COLOR 0xFFFFFFFF
+#define LABEL_BG_COLOR 0x000000FF
 #define FONT_FAMILY "sans-serif"
 
 static void noop() {
@@ -719,13 +721,16 @@ static const char usage[] =
 	"  -c #rrggbbaa Set border color.\n"
 	"  -s #rrggbbaa Set selection color.\n"
 	"  -B #rrggbbaa Set option box color.\n"
+	"  -l #rrggbbaa Set label text color.\n"
+	"  -L #rrggbbaa Set label background color.\n"
 	"  -F s         Set the font family for the dimensions.\n"
 	"  -w n         Set border weight.\n"
 	"  -f s         Set output format.\n"
 	"  -o           Select a display output.\n"
 	"  -p           Select a single point.\n"
 	"  -r           Restrict selection to predefined boxes.\n"
-	"  -a w:h       Force aspect ratio.\n";
+	"  -a w:h       Force aspect ratio.\n"
+	"  -P           Position labels on the option boxes.\n";
 
 uint32_t parse_color(const char *color) {
 	if (color[0] == '#') {
@@ -745,6 +750,27 @@ uint32_t parse_color(const char *color) {
 	return res;
 }
 
+
+enum slurp_label_anchor parse_label_anchor(const char *anchor) {
+	enum slurp_label_anchor label_anchor = ANCHOR_NONE;
+	if (strstr(anchor, "top") != NULL) {
+		label_anchor |= ANCHOR_TOP;
+	}
+	if (strstr(anchor, "bottom") != NULL) {
+		label_anchor |= ANCHOR_BOTTOM;
+	}
+	if (strstr(anchor, "left") != NULL) {
+		label_anchor |= ANCHOR_LEFT;
+	}
+	if (strstr(anchor, "right") != NULL) {
+		label_anchor |= ANCHOR_RIGHT;
+	}
+	if (strstr(anchor, "center") != NULL) {
+		label_anchor |= ANCHOR_TOP  | ANCHOR_BOTTOM | ANCHOR_LEFT | ANCHOR_RIGHT;
+	}
+	return label_anchor;
+}
+
 static struct slurp_output *output_from_box(const struct slurp_box *box, struct wl_list *outputs) {
 	struct slurp_output *output;
 	wl_list_for_each(output, outputs, link) {
@@ -887,21 +913,24 @@ int main(int argc, char *argv[]) {
 			.border = BORDER_COLOR,
 			.selection = SELECTION_COLOR,
 			.choice = BG_COLOR,
+			.label_text = LABEL_COLOR,
+			.label_background = LABEL_BG_COLOR,
 		},
 		.border_weight = 2,
 		.display_dimensions = false,
 		.restrict_selection = false,
 		.resizing_selection = false,
 		.fixed_aspect_ratio = false,
 		.aspect_ratio = 0,
-		.font_family = FONT_FAMILY
+		.font_family = FONT_FAMILY,
+		.label_anchor = ANCHOR_NONE
 	};
 
 	int opt;
 	char *format = "%x,%y %wx%h\n";
 	bool output_boxes = false;
 	int w, h;
-	while ((opt = getopt(argc, argv, "hdb:c:s:B:w:proa:f:F:")) != -1) {
+	while ((opt = getopt(argc, argv, "hdb:c:s:B:l:L:w:proa:f:F:P:")) != -1) {
 		switch (opt) {
 		case 'h':
 			printf("%s", usage);
@@ -921,12 +950,21 @@ int main(int argc, char *argv[]) {
 		case 'B':
 			state.colors.choice = parse_color(optarg);
 			break;
+		case 'l':
+			state.colors.label_text = parse_color(optarg);
+			break;
+		case 'L':
+			state.colors.label_background = parse_color(optarg);
+			break;
 		case 'f':
 			format = optarg;
 			break;
 		case 'F':
 			state.font_family = optarg;
 			break;
+		case 'P':
+			state.label_anchor = parse_label_anchor(optarg);
+			break;
 		case 'w': {
 			errno = 0;
 			char *endptr;

meson.build

@@ -12,6 +12,7 @@ add_project_arguments('-Wno-unused-parameter', language: 'c')
 cc = meson.get_compiler('c')
 
 cairo = dependency('cairo')
+math = cc.find_library('m')
 realtime = cc.find_library('rt')
 wayland_client = dependency('wayland-client')
 wayland_cursor = dependency('wayland-cursor')
@@ -30,6 +31,7 @@ executable(
 	],
 	dependencies: [
 		cairo,
+		math,
 		realtime,
 		wayland_client,
 		wayland_cursor,

render.c

@@ -1,11 +1,16 @@
 #include <cairo/cairo.h>
+#include <math.h>
 #include <stdio.h>
 #include <stdlib.h>
 
 #include "pool-buffer.h"
 #include "render.h"
 #include "slurp.h"
 
+#define LABEL_BOX_PADDING 10
+#define LABEL_HORIZONTAL_MARGING 10
+#define LABEL_VERTICAL_MARGING 20
+
 static void set_source_u32(cairo_t *cairo, uint32_t color) {
 	cairo_set_source_rgba(cairo, (color >> (3 * 8) & 0xFF) / 255.0,
 		(color >> (2 * 8) & 0xFF) / 255.0,
@@ -19,6 +24,45 @@ static void draw_rect(cairo_t *cairo, struct slurp_box *box, uint32_t color) {
 			box->width, box->height);
 }
 
+static void draw_rect_label(cairo_t *cairo, struct slurp_box *box, enum slurp_label_anchor anchor,
+		uint32_t text_color, uint32_t background_color, const char *font_family, const char *text) {
+	if (anchor == ANCHOR_NONE)
+		return;
+	cairo_select_font_face(cairo, font_family,
+						 CAIRO_FONT_SLANT_NORMAL,
+						 CAIRO_FONT_WEIGHT_NORMAL);
+	cairo_set_font_size(cairo, 20);
+	cairo_text_extents_t extents;
+	cairo_text_extents(cairo, text, &extents);
+	struct slurp_box labelbox = { 0 };
+	labelbox.width = ceil(extents.width) + 2*LABEL_BOX_PADDING;
+	labelbox.height = ceil(extents.height) + 2*LABEL_BOX_PADDING;
+	labelbox.x = box->x + (box->width - labelbox.width) / 2;
+	labelbox.y = box->y + (box->height - labelbox.height) / 2;
+
+	if (anchor & ANCHOR_TOP && anchor & ANCHOR_BOTTOM) {
+		// Nothing to do
+	} else if (anchor & ANCHOR_TOP) {
+		labelbox.y = box->y + LABEL_VERTICAL_MARGING;
+	} else if (anchor & ANCHOR_BOTTOM) {
+		labelbox.y = box->y + box->height - LABEL_VERTICAL_MARGING - labelbox.height;
+	}
+	if (anchor & ANCHOR_LEFT && anchor & ANCHOR_RIGHT) {
+		// Nothing to do
+	} else if (anchor & ANCHOR_LEFT) {
+		labelbox.x = box->x + LABEL_HORIZONTAL_MARGING;
+	} else if (anchor & ANCHOR_RIGHT) {
+		labelbox.x = box->x + box->width - LABEL_HORIZONTAL_MARGING - labelbox.width;
+	}
+
+	draw_rect(cairo, &labelbox, background_color);
+	cairo_fill(cairo);
+	set_source_u32(cairo, text_color);
+	cairo_move_to(cairo, labelbox.x + LABEL_BOX_PADDING,
+					labelbox.y + LABEL_BOX_PADDING + ceil(extents.height));
+	cairo_show_text(cairo, text);
+}
+
 static void box_layout_to_output(struct slurp_box *box, struct slurp_output *output) {
 	box->x -= output->logical_geometry.x;
 	box->y -= output->logical_geometry.y;
@@ -43,6 +87,9 @@ void render(struct slurp_output *output) {
 			box_layout_to_output(&b, output);
 			draw_rect(cairo, &b, state->colors.choice);
 			cairo_fill(cairo);
+			if (b.label)
+				draw_rect_label(cairo, &b, state->label_anchor,
+						state->colors.label_text, state->colors.label_background, state->font_family, b.label);
 		}
 	}
 
@@ -64,6 +111,9 @@ void render(struct slurp_output *output) {
 
 		draw_rect(cairo, &b, state->colors.selection);
 		cairo_fill(cairo);
+		if (b.label)
+				draw_rect_label(cairo, &b, state->label_anchor,
+						state->colors.label_text, state->colors.label_background, state->font_family, b.label);
 
 		// Draw border
 		cairo_set_line_width(cairo, state->border_weight);

slurp.1.scd

@@ -44,6 +44,12 @@ held, the selection is moved instead of being resized.
 	Set color for highlighting predefined rectangles from standard input when not
 	selected. Default is #FFFFFF40.
 
+*-l* _color_
+	Set text color for labels. See *COLORS* for more detail.
+
+*-L* _color_
+	Set background color for labels. See *COLORS* for more detail.
+
 *-F* _font family_
 	Set the font family name when displaying the dimensions box. Only useful
 	when combined with the -d option. The available font family names guaranteed
@@ -56,6 +62,9 @@ held, the selection is moved instead of being resized.
 *-f* _format_
 	Set format. See *FORMAT* for more detail.
 
+*-P* _anchor_
+	Set postion anchor for the labels. See *ANCHOR* for more detail.
+
 *-p*
 	Select a single pixel instead of a rectangle. This mode ignores any
 	predefined rectangles read from the standard input.
@@ -108,6 +117,15 @@ Interpreted sequences are:
 
 The default format is "%x,%y %wx%h\\n".
 
+# ANCHOR
+
+Valid values are:
+
+none, top, bottom, left, right, center
+
+Combinations of these keywords chained together are possible, eg. top-right to
+position the label in the top right corner.
+
 # KEYBOARD CONTROLS
 
 The following keyboard actions can be used during selection: