zoomSurface support; fixes #673

src/library_sdl.js

@@ -966,6 +966,16 @@ var LibrarySDL = {
     return _SDL_UpperBlit(src, srcrect, dst, dstrect);
   },
 
+  zoomSurface: function(src, x, y, smooth) {
+    var srcData = SDL.surfaces[src];
+    var w = srcData.width*x;
+    var h = srcData.height*y;
+    var ret = SDL.makeSurface(w, h, srcData.flags, false, 'zoomSurface');
+    var dstData = SDL.surfaces[ret];
+    dstData.ctx.drawImage(srcData.canvas, 0, 0, w, h);
+    return ret;
+  },
+
   SDL_SetAlpha: function(surf, flag, alpha) {
     SDL.surfaces[surf].alpha = alpha;
   },

system/include/SDL/SDL_rotozoom.h

@@ -0,0 +1,123 @@
+/*  
+
+SDL_rotozoom.c: rotozoomer, zoomer and shrinker for 32bit or 8bit surfaces
+
+Copyright (C) 2001-2011  Andreas Schiffler
+
+This software is provided 'as-is', without any express or implied
+warranty. In no event will the authors be held liable for any damages
+arising from the use of this software.
+
+Permission is granted to anyone to use this software for any purpose,
+including commercial applications, and to alter it and redistribute it
+freely, subject to the following restrictions:
+
+   1. The origin of this software must not be misrepresented; you must not
+   claim that you wrote the original software. If you use this software
+   in a product, an acknowledgment in the product documentation would be
+   appreciated but is not required.
+
+   2. Altered source versions must be plainly marked as such, and must not be
+   misrepresented as being the original software.
+
+   3. This notice may not be removed or altered from any source
+   distribution.
+
+Andreas Schiffler -- aschiffler at ferzkopp dot net
+
+*/
+
+#ifndef _SDL_rotozoom_h
+#define _SDL_rotozoom_h
+
+#include <math.h>
+
+/* Set up for C function definitions, even when using C++ */
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifndef M_PI
+#define M_PI	3.141592654
+#endif
+
+#include "SDL.h"
+
+	/* ---- Defines */
+
+	/*!
+	\brief Disable anti-aliasing (no smoothing).
+	*/
+#define SMOOTHING_OFF		0
+
+	/*!
+	\brief Enable anti-aliasing (smoothing).
+	*/
+#define SMOOTHING_ON		1
+
+	/* ---- Function Prototypes */
+
+#ifdef _MSC_VER
+#  if defined(DLL_EXPORT) && !defined(LIBSDL_GFX_DLL_IMPORT)
+#    define SDL_ROTOZOOM_SCOPE __declspec(dllexport)
+#  else
+#    ifdef LIBSDL_GFX_DLL_IMPORT
+#      define SDL_ROTOZOOM_SCOPE __declspec(dllimport)
+#    endif
+#  endif
+#endif
+#ifndef SDL_ROTOZOOM_SCOPE
+#  define SDL_ROTOZOOM_SCOPE extern
+#endif
+
+	/* 
+
+	Rotozoom functions
+
+	*/
+
+	SDL_ROTOZOOM_SCOPE SDL_Surface *rotozoomSurface(SDL_Surface * src, double angle, double zoom, int smooth);
+
+	SDL_ROTOZOOM_SCOPE SDL_Surface *rotozoomSurfaceXY
+		(SDL_Surface * src, double angle, double zoomx, double zoomy, int smooth);
+
+
+	SDL_ROTOZOOM_SCOPE void rotozoomSurfaceSize(int width, int height, double angle, double zoom, int *dstwidth,
+		int *dstheight);
+
+	SDL_ROTOZOOM_SCOPE void rotozoomSurfaceSizeXY
+		(int width, int height, double angle, double zoomx, double zoomy, 
+		int *dstwidth, int *dstheight);
+
+	/* 
+
+	Zooming functions
+
+	*/
+
+	SDL_ROTOZOOM_SCOPE SDL_Surface *zoomSurface(SDL_Surface * src, double zoomx, double zoomy, int smooth);
+
+	SDL_ROTOZOOM_SCOPE void zoomSurfaceSize(int width, int height, double zoomx, double zoomy, int *dstwidth, int *dstheight);
+
+	/* 
+
+	Shrinking functions
+
+	*/     
+
+	SDL_ROTOZOOM_SCOPE SDL_Surface *shrinkSurface(SDL_Surface * src, int factorx, int factory);
+
+	/* 
+
+	Specialized rotation functions
+
+	*/
+
+	SDL_ROTOZOOM_SCOPE SDL_Surface* rotateSurface90Degrees(SDL_Surface* src, int numClockwiseTurns);
+
+	/* Ends C function definitions when using C++ */
+#ifdef __cplusplus
+}
+#endif
+
+#endif				/* _SDL_rotozoom_h */

tests/runner.py

@@ -9261,6 +9261,10 @@ def test_sdl_canvas_twice(self):
     def test_sdl_maprgba(self):
       self.btest('sdl_maprgba.c', reference='sdl_maprgba.png', reference_slack=3)
 
+    def test_sdl_rotozoom(self):
+      shutil.copyfile(path_from_root('tests', 'screenshot.png'), os.path.join(self.get_dir(), 'example.png'))
+      self.btest('sdl_rotozoom.c', reference='sdl_rotozoom.png', args=['--preload-file', 'example.png'])
+
     def zzztest_sdl_canvas_palette_2(self): # XXX disabled until we have proper automation
       open(os.path.join(self.get_dir(), 'sdl_canvas_palette_2.c'), 'w').write(self.with_report_result(open(path_from_root('tests', 'sdl_canvas_palette_2.c')).read()))
       open(os.path.join(self.get_dir(), 'pre.js'), 'w').write('Module[\'preRun\'] = function() { SDL.defaults.copyOnLock = false }')

tests/sdl_rotozoom.c

@@ -0,0 +1,48 @@
+#include "SDL/SDL.h"
+#include "SDL/SDL_image.h"
+#include "SDL/SDL_rotozoom.h"
+
+#ifdef EMSCRIPTEN
+#include "emscripten.h"
+#endif
+
+SDL_Surface *screen;
+SDL_Surface *sprite[4];
+
+void mainloop() {
+    int i;
+    SDL_Rect rect = { 0, 0, 100, 100 };
+    for (i = 0; i < 4; i++) {
+        rect.x = i & 1 ? 200 : 0;
+        rect.y = i & 2 ? 200 : 0;
+        SDL_BlitSurface(sprite[i], 0, screen, &rect);
+        SDL_UpdateRect(screen, 0, 0, 0, 0);
+    }
+}
+
+int main(int argc, char **argv) {
+    SDL_Init(SDL_INIT_VIDEO);
+
+    screen = SDL_SetVideoMode(400, 400, 32, SDL_SWSURFACE);
+
+    sprite[0] = IMG_Load("example.png");
+    sprite[1] = SDL_CreateRGBSurface(SDL_SWSURFACE, 100, 100, 32, 0xFF000000, 0xFF0000, 0xFF00, 0xFF);
+    SDL_FillRect(sprite[1], 0, 0xA0A0A0A0);
+    sprite[2] = zoomSurface(sprite[0], 0.5, 0.5, SMOOTHING_ON);
+    sprite[3] = zoomSurface(sprite[1], 0.5, 0.5, SMOOTHING_ON);
+
+    mainloop();
+
+#ifndef EMSCRIPTEN
+    SDL_Event evt;
+    while (1) {
+       if (SDL_PollEvent(&evt) != 0 && evt.type == SDL_QUIT) break;
+       //mainloop();
+       SDL_Delay(33);
+    }
+#endif
+
+    SDL_Quit();
+
+    return 1;
+}