Add support for crosshairs

include/slurp.h

@@ -49,6 +49,7 @@ struct slurp_state {
 	uint32_t border_weight;
 	bool display_dimensions;
 	bool single_point;
+	bool crosshairs;
 	struct wl_list boxes; // slurp_box::link
 
 	struct slurp_box result;

main.c

@@ -76,12 +76,14 @@ static void pointer_handle_leave(void *data, struct wl_pointer *wl_pointer,
 }
 
 static void seat_set_outputs_dirty(struct slurp_seat *seat) {
+	struct slurp_state *state = seat->state;
 	struct slurp_output *output;
 	wl_list_for_each(output, &seat->state->outputs, link) {
 		if (box_intersect(&output->logical_geometry,
 			&seat->pointer_selection.selection) ||
 		    box_intersect(&output->logical_geometry,
-			&seat->touch_selection.selection)) {
+			&seat->touch_selection.selection) ||
+			state->crosshairs) {
 			set_output_dirty(output);
 		}
 	}
@@ -121,8 +123,10 @@ static void handle_active_selection_motion(struct slurp_seat *seat, struct slurp
 static void pointer_handle_motion(void *data, struct wl_pointer *wl_pointer,
 		uint32_t time, wl_fixed_t surface_x, wl_fixed_t surface_y) {
 	struct slurp_seat *seat = data;
+	struct slurp_state *state = seat->state;
+
 	// the places the cursor moved away from are also dirty
-	if (seat->pointer_selection.has_selection) {
+	if (seat->pointer_selection.has_selection || state->crosshairs) {
 		seat_set_outputs_dirty(seat);
 	}
 
@@ -153,7 +157,7 @@ static void pointer_handle_motion(void *data, struct wl_pointer *wl_pointer,
 		break;
 	}
 
-	if (seat->pointer_selection.has_selection) {
+	if (seat->pointer_selection.has_selection || state->crosshairs) {
 		seat_set_outputs_dirty(seat);
 	}
 }
@@ -702,7 +706,7 @@ int main(int argc, char *argv[]) {
 
 	int opt;
 	char *format = "%x,%y %wx%h";
-	while ((opt = getopt(argc, argv, "hdb:c:s:w:pf:")) != -1) {
+	while ((opt = getopt(argc, argv, "hdb:c:s:w:pf:x")) != -1) {
 		switch (opt) {
 		case 'h':
 			printf("%s", usage);
@@ -735,6 +739,9 @@ int main(int argc, char *argv[]) {
 		case 'p':
 			state.single_point = true;
 			break;
+		case 'x':
+			state.crosshairs = true;
+			break;
 		default:
 			printf("%s", usage);
 			return EXIT_FAILURE;

render.c

@@ -31,6 +31,21 @@ void render(struct slurp_output *output) {
 				&seat->touch_selection :
 				&seat->pointer_selection;
 
+		if (!current_selection->has_selection && state->crosshairs) {
+			if (output->logical_geometry.x <= current_selection->x &&
+					output->logical_geometry.x + output->logical_geometry.width >= current_selection->x &&
+					output->logical_geometry.y <= current_selection->y &&
+					output->logical_geometry.y + output->logical_geometry.height >= current_selection->y) {
+
+				set_source_u32(cairo, state->colors.selection);
+				cairo_rectangle(cairo, 0, current_selection->y, output->logical_geometry.width, 1);
+				cairo_fill(cairo);
+				cairo_rectangle(cairo, current_selection->x - output->logical_geometry.x,
+						output->logical_geometry.y, 1, output->logical_geometry.height);
+				cairo_fill(cairo);
+			}
+		}
+
 		if (!seat->wl_pointer) {
 			continue;
 		}