pebble-virtual-screen

A virtual screen implementation for the Pebble smartwatch.

Use this library to test the layout for large screens (e.g. Pebble Time 2) on smaller screens (e.g. Pebble Time).

There are several modes available:

VIRTUAL_SCREEN_MODE_DIRECT
The large screen is centered on the position the watch has when the app starts. You can scroll the screen around by moving the watch.

VIRTUAL_SCREEN_MODE_AUTO
The large screen is autmatically moved to the next corner every second. Use this for testing in the emulator.

VIRTUAL_SCREEN_MODE_{CENTERED,TOP_LEFT,TOP_RIGHT,BOTTOM_LEFT,BOTTOM_RIGHT}
The large screen remains in a fixed position.

To use a virtual screen you just have to use the Layer returned by virtual_screen_init instead of the root layer you normally use. If you use graphics_capture_frame_buffer to modify the framebuffer you also have to manually apply the offset returned by virtual_screen_get_offset.

You can use the VIRTUAL_SCREEN define to determine whether or not the virtual screen is used. The define is set if pebble-virtual-screen.h is included.

This is how VIRTUAL_SCREEN_MODE_AUTO looks in CloudPebble:

Usage example:

#include <pebble-virtual-screen/pebble-virtual-screen.h>

static void my_window_load(Window *window) {
  Layer* root_layer = window_get_root_layer(window);
  GRect root_layer_bounds = layer_get_bounds(root_layer);

#ifdef VIRTUAL_SCREEN
  Layer* real_root = root_layer;
  root_layer = virtual_screen_init(root_layer_bounds, VIRTUAL_SCREEN_SIZE_EMERY, VIRTUAL_SCREEN_MODE_AUTO);
  root_layer_bounds = layer_get_bounds(root_layer);
#endif // VIRTUAL_SCREEN

  background_layer = layer_create(root_layer_bounds);
  layer_set_update_proc(background_layer, background_layer_draw);
  layer_add_child(root_layer, background_layer);
  
  time_layer = layer_create(GRectZero);
  layer_set_update_proc(time_layer, time_layer_draw);
  layer_add_child(root_layer, time_layer);

  date_layer = layer_create(GRectZero);
  layer_set_update_proc(date_layer, date_layer_draw);
  layer_add_child(root_layer, date_layer);

#ifdef VIRTUAL_SCREEN
  layer_add_child(real_root, root_layer);
#endif // VIRTUAL_SCREEN
}