implement cursor and device geometry mapping

examples/config.c

@@ -7,6 +7,7 @@
 #include <string.h>
 #include <unistd.h>
 #include <wlr/util/log.h>
+#include <wlr/types/wlr_geometry.h>
 #include "shared.h"
 #include "config.h"
 #include "ini.h"
@@ -21,6 +22,64 @@ static void usage(const char *name, int ret) {
 	exit(ret);
 }
 
+static struct wlr_geometry *parse_geometry(const char *str) {
+	// format: {width}x{height}+{x}+{y}
+	if (strlen(str) > 255l) {
+		wlr_log(L_ERROR, "cannot parse geometry string, too long");
+		return NULL;
+	}
+
+	char *buf = strdup(str);
+	struct wlr_geometry *geo = calloc(1, sizeof(struct wlr_geometry));
+
+	bool has_width, has_height, has_x, has_y;
+	char *pch = strtok(buf, "x+");
+	while (pch != NULL) {
+		errno = 0;
+		char *endptr;
+		long val = strtol(pch, &endptr, 0);
+
+		if ((errno == ERANGE && (val == LONG_MAX || val == LONG_MIN))
+				|| (errno != 0 && val == 0)) {
+			goto invalid_input;
+		}
+
+		if (endptr == pch) {
+			goto invalid_input;
+		}
+
+		if (!has_width) {
+			geo->width = val;
+			has_width = true;
+		} else if (!has_height) {
+			geo->height = val;
+			has_height = true;
+		} else if (!has_x) {
+			geo->x = val;
+			has_x = true;
+		} else if (!has_y) {
+			geo->y = val;
+			has_y = true;
+		} else {
+			goto invalid_input;
+		}
+		pch = strtok(NULL, "x+");
+	}
+
+	if (!has_width || !has_height || !has_x || !has_y) {
+		goto invalid_input;
+	}
+
+	free(buf);
+	return geo;
+
+invalid_input:
+	wlr_log(L_ERROR, "could not parse geometry string: %s", str);
+	free(buf);
+	free(geo);
+	return NULL;
+}
+
 static const char *output_prefix = "output:";
 static const char *device_prefix = "device:";
 
@@ -71,6 +130,11 @@ static int config_ini_handler(void *user, const char *section, const char *name,
 	} else if (strcmp(section, "cursor") == 0) {
 		if (strcmp(name, "map-to-output") == 0) {
 			config->cursor.mapped_output = strdup(value);
+		} else if (strcmp(name, "geometry") == 0) {
+			if (config->cursor.mapped_geo) {
+				free(config->cursor.mapped_geo);
+			}
+			config->cursor.mapped_geo = parse_geometry(value);
 		} else {
 			wlr_log(L_ERROR, "got unknown cursor config: %s", name);
 		}
@@ -97,6 +161,11 @@ static int config_ini_handler(void *user, const char *section, const char *name,
 				free(dc->mapped_output);
 			}
 			dc->mapped_output = strdup(value);
+		} else if (strcmp(name, "geometry") == 0) {
+			if (dc->mapped_geo) {
+				free(dc->mapped_geo);
+			}
+			dc->mapped_geo = parse_geometry(value);
 		} else {
 			wlr_log(L_ERROR, "got unknown device config: %s", name);
 		}
@@ -166,6 +235,9 @@ void example_config_destroy(struct example_config *config) {
 		if (dc->mapped_output) {
 			free(dc->mapped_output);
 		}
+		if (dc->mapped_geo) {
+			free(dc->mapped_geo);
+		}
 		free(dc);
 	}
 
@@ -175,6 +247,9 @@ void example_config_destroy(struct example_config *config) {
 	if (config->cursor.mapped_output) {
 		free(config->cursor.mapped_output);
 	}
+	if (config->cursor.mapped_geo) {
+		free(config->cursor.mapped_geo);
+	}
 	free(config);
 }
 

examples/config.h

@@ -15,12 +15,14 @@ struct output_config {
 struct device_config {
 	char *name;
 	char *mapped_output;
+	struct wlr_geometry *mapped_geo;
 	struct wl_list link;
 };
 
 struct example_config {
 	struct {
 		char *mapped_output;
+		struct wlr_geometry *mapped_geo;
 	} cursor;
 
 	struct wl_list outputs;

examples/pointer.c

@@ -63,14 +63,21 @@ static void handle_output_frame(struct output_state *output, struct timespec *ts
 
 static void configure_devices(struct sample_state *sample) {
 	struct sample_input_device *dev;
-	// reset device to output mappings
+	struct device_config *dc;
+
+	// reset device mappings
 	wl_list_for_each(dev, &sample->devices, link) {
 		wlr_cursor_map_input_to_output(sample->cursor, dev->device, NULL);
+		wl_list_for_each(dc, &sample->config->devices, link) {
+			if (strcmp(dev->device->name, dc->name) == 0) {
+				wlr_cursor_map_input_to_region(sample->cursor, dev->device,
+					dc->mapped_geo);
+			}
+		}
 	}
 
 	struct output_state *ostate;
 	wl_list_for_each(ostate, &sample->compositor->outputs, link) {
-		struct device_config *dc;
 		wl_list_for_each(dc, &sample->config->devices, link) {
 			// configure device to output mappings
 			if (dc->mapped_output &&
@@ -123,7 +130,8 @@ static void handle_output_remove(struct output_state *ostate) {
 
 	configure_devices(sample);
 
-	if (strcmp(sample->config->cursor.mapped_output, ostate->output->name) == 0) {
+	char *mapped_output = sample->config->cursor.mapped_output;
+	if (mapped_output && strcmp(mapped_output, ostate->output->name) == 0) {
 		wlr_cursor_map_to_output(sample->cursor, NULL);
 	}
 }
@@ -216,6 +224,7 @@ int main(int argc, char *argv[]) {
 
 	state.config = parse_args(argc, argv);
 	state.cursor = wlr_cursor_init();
+	wlr_cursor_map_to_region(state.cursor, state.config->cursor.mapped_geo);
 	wl_list_init(&state.devices);
 
 	wl_signal_add(&state.cursor->events.motion, &state.cursor_motion);

examples/wlr-example.ini.example

@@ -34,8 +34,12 @@ y=232
 # ~~~~~~~~~~~~~~~~~~~~
 # Value "map-to-output" specifies the output to which the cursor is
 # constrained.
+#
+# Value "geometry" specifies the geometry (widthxheight+x+y) to which the cursor
+# is constrained.
 [cursor]
 map-to-output=HDMI-A-1
+geometry=500x700+50+50
 
 # Device Configuration
 # ~~~~~~~~~~~~~~~~~~~~
@@ -43,7 +47,11 @@ map-to-output=HDMI-A-1
 # name given to this device. See a log file for device names.
 #
 # Value "map-to-output" specifies the output to which the device is constrained.
+#
+# Value "geometry" specifies the geometry (widthxheight+x+y) to which the device
+# is constrained.
 [device:Razer Razer DeathAdder 2013]
 map-to-output=DP-1
+geometry=500x700+50+50
 
 # vim:filetype=dosini

include/wlr/types/wlr_cursor.h

@@ -4,6 +4,7 @@
 #include <wlr/types/wlr_output.h>
 #include <wlr/types/wlr_output_layout.h>
 #include <wlr/types/wlr_input_device.h>
+#include <wlr/types/wlr_geometry.h>
 #include <wlr/xcursor.h>
 
 struct wlr_cursor_state;
@@ -87,12 +88,13 @@ void wlr_cursor_map_input_to_output(struct wlr_cursor *cur,
 /**
  * Maps this cursor to an arbitrary region on the associated wlr_output_layout.
  */
-//void wlr_cursor_map_to_region(struct wlr_cursor *cur, struct wlr_geometry *geo);
+void wlr_cursor_map_to_region(struct wlr_cursor *cur, struct wlr_geometry *geo);
 
 /**
  * Maps inputs from this input device to an arbitrary region on the associated
  * wlr_output_layout.
  */
-//void wlr_cursor_map_input_to_region(struct wlr_cursor *cur, struct wlr_input_device *dev, struct wlr_geometry *geo);
+void wlr_cursor_map_input_to_region(struct wlr_cursor *cur,
+		struct wlr_input_device *dev, struct wlr_geometry *geo);
 
 #endif

include/wlr/types/wlr_geometry.h

@@ -0,0 +1,12 @@
+#ifndef _WLR_TYPES_GEOMETRY_H
+#define _WLR_TYPES_GEOMETRY_H
+
+struct wlr_geometry {
+	int x, y;
+	int width, height;
+};
+
+void wlr_geometry_closest_boundary(struct wlr_geometry *geo, double x, double y,
+		int *dest_x, int *dest_y, double *distance);
+
+#endif

types/meson.build

@@ -16,6 +16,7 @@ lib_wlr_types = static_library('wlr_types', files(
     'wlr_xdg_shell_v6.c',
     'wlr_wl_shell.c',
     'wlr_compositor.c',
+	'wlr_geometry.c',
   ),
   include_directories: wlr_inc,
   dependencies: [wayland_server, pixman, wlr_protos])

types/wlr_cursor.c

@@ -12,6 +12,7 @@ struct wlr_cursor_device {
 	struct wlr_input_device *device;
 	struct wl_list link;
 	struct wlr_output *mapped_output;
+	struct wlr_geometry *mapped_geometry;
 
 	struct wl_listener motion;
 	struct wl_listener motion_absolute;
@@ -24,6 +25,7 @@ struct wlr_cursor_state {
 	struct wlr_output_layout *layout;
 	struct wlr_xcursor *xcursor;
 	struct wlr_output *mapped_output;
+	struct wlr_geometry *mapped_geometry;
 };
 
 struct wlr_cursor *wlr_cursor_init() {
@@ -145,6 +147,25 @@ void wlr_cursor_move(struct wlr_cursor *cur, struct wlr_input_device *dev,
 	double x = cur->x + delta_x;
 	double y = cur->y + delta_y;
 
+	// cursor geometry constraints
+	if (cur->state->mapped_geometry) {
+		int closest_x, closest_y;
+		wlr_geometry_closest_boundary(cur->state->mapped_geometry, x, y,
+			&closest_x, &closest_y, NULL);
+		x = closest_x;
+		y = closest_y;
+	}
+
+	// device constraints
+	if (c_device->mapped_geometry) {
+		int closest_x, closest_y;
+		wlr_geometry_closest_boundary(c_device->mapped_geometry, x, y,
+			&closest_x, &closest_y, NULL);
+		x = closest_x;
+		y = closest_y;
+	}
+
+	// layout constraints
 	struct wlr_output *output;
 	output = wlr_output_layout_output_at(cur->state->layout, x, y);
 
@@ -271,3 +292,17 @@ void wlr_cursor_map_input_to_output(struct wlr_cursor *cur,
 
 	c_device->mapped_output = output;
 }
+
+void wlr_cursor_map_to_region(struct wlr_cursor *cur, struct wlr_geometry *geo) {
+	cur->state->mapped_geometry = geo;
+}
+
+void wlr_cursor_map_input_to_region(struct wlr_cursor *cur,
+		struct wlr_input_device *dev, struct wlr_geometry *geo) {
+	struct wlr_cursor_device *c_device = get_cursor_device(cur, dev);
+	if (!c_device) {
+		wlr_log(L_ERROR, "Cannot map device \"%s\" to geometry (not found in this cursor)", dev->name);
+		return;
+	}
+	c_device->mapped_geometry = geo;
+}

types/wlr_geometry.c

@@ -0,0 +1,36 @@
+#include <limits.h>
+#include <stdlib.h>
+#include <math.h>
+#include <wlr/types/wlr_geometry.h>
+
+static double get_distance(double x1, double y1, double x2, double y2) {
+	double distance;
+	distance = sqrt((x1 - x2) * (x1 - x2) + (y1 - y2) * (y1 - y2));
+	return distance;
+}
+
+void wlr_geometry_closest_boundary(struct wlr_geometry *geo, double x, double y,
+		int *dest_x, int *dest_y, double *distance) {
+	// find the closest x point
+	if (x < geo->x) {
+		*dest_x = geo->x;
+	} else if (x > geo->x + geo->width) {
+		*dest_x = geo->x + geo->width;
+	} else {
+		*dest_x = x;
+	}
+
+	// find closest y point
+	if (y < geo->y) {
+		*dest_y = geo->y;
+	} else if (y > geo->y + geo->height) {
+		*dest_y = geo->y + geo->height;
+	} else {
+		*dest_y = y;
+	}
+
+	// calculate distance
+	if (distance) {
+		*distance = get_distance(*dest_x, *dest_y, x, y);
+	}
+}

types/wlr_output_layout.c

@@ -149,6 +149,7 @@ void wlr_output_layout_closest_boundary(struct wlr_output_layout *layout,
 		wlr_output_effective_resolution(l_output->output, &width, &height);
 
 		// find the closest x point
+		// TODO use wlr_geometry_closest_boundary
 		if (x < l_output->x) {
 			output_x = l_output->x;
 		} else if (x > l_output->x + width) {