Merge pull request #1556 from ToadKing/getcanvassize

Ability to get current canvas size

3 files changed, 24 insertions, 0 deletions

diff --git a/src/library_browser.js b/src/library_browser.js
index 558c9a59..591a3c11 100644
--- a/src/library_browser.js
+++ b/src/library_browser.js
@@ -821,6 +821,13 @@ mergeInto(LibraryManager.library, {
   emscripten_set_canvas_size: function(width, height) {
     Browser.setCanvasSize(width, height);
   },
+  
+  emscripten_get_canvas_size: function(width, height, isFullscreen) {
+    var canvas = Module['canvas'];
+    {{{ makeSetValue('width', '0', 'canvas.width', 'i32') }}};
+    {{{ makeSetValue('height', '0', 'canvas.height', 'i32') }}};
+    {{{ makeSetValue('isFullscreen', '0', 'Browser.isFullScreen ? 1 : 0', 'i32') }}};
+  },
 
   emscripten_get_now: function() {
     if (ENVIRONMENT_IS_NODE) {
diff --git a/system/include/emscripten/emscripten.h b/system/include/emscripten/emscripten.h
index 1ed4c721..1b9a8f25 100644
--- a/system/include/emscripten/emscripten.h
+++ b/system/include/emscripten/emscripten.h
@@ -170,6 +170,12 @@ void emscripten_hide_mouse();
 void emscripten_set_canvas_size(int width, int height);
 
 /*
+ * Get the current pixel width and height of the <canvas> element
+ * as well as whether the canvas is fullscreen or not.
+ */
+void emscripten_get_canvas_size(int *width, int *height, int *isFullscreen);
+
+/*
  * Returns the highest-precision representation of the
  * current time that the browser provides. This uses either
  * Date.now or performance.now. The result is *not* an
diff --git a/tests/sdl_canvas.c b/tests/sdl_canvas.c
index 10044ff4..6bd659b8 100644
--- a/tests/sdl_canvas.c
+++ b/tests/sdl_canvas.c
@@ -1,4 +1,5 @@
 #include <stdio.h>
+#include <stdlib.h>
 #include <SDL/SDL.h>
 #include <SDL/SDL_ttf.h>
 #include <emscripten.h>
@@ -43,6 +44,16 @@ int main(int argc, char **argv) {
   SDL_Flip(screen); 
 
   SDL_LockSurface(screen);
+
+  int width, height, isFullscreen;
+  emscripten_get_canvas_size(&width, &height, &isFullscreen);
+
+  if (width != 600 && height != 450)
+  {
+    printf("error: wrong width/height\n");
+    abort();
+  }
+
   int sum = 0;
   for (int i = 0; i < screen->h; i++) {
     sum += *((char*)screen->pixels + i*screen->w*4 + i*4 + 0);