sdl2: add support for reading image from memory

kivy/core/image/_img_sdl2.pyx

@@ -38,9 +38,8 @@ def save(filename, w, h, fmt, pixels, flipped):
     IMG_SavePNG(image, c_filename)
     SDL_FreeSurface(image)
 
-def load(filename):
-    cdef bytes c_filename = filename.encode('utf-8')
-    cdef SDL_Surface *image = IMG_Load(c_filename)
+
+cdef load_from_surface(SDL_Surface *image):
     cdef SDL_Surface *image2 = NULL
     cdef SDL_Surface *fimage = NULL
     cdef SDL_PixelFormat pf
@@ -48,7 +47,6 @@ def load(filename):
 
     try:
         if image == NULL:
-            #print 'UNABLE TO LOAD O_o?'
             return None
 
         fmt = ''
@@ -104,7 +102,38 @@ def load(filename):
         return (fimage.w, fimage.h, fmt, pixels, fimage.pitch)
 
     finally:
-        if image:
-            SDL_FreeSurface(image)
         if image2:
             SDL_FreeSurface(image2)
+
+
+def load_from_filename(filename):
+    cdef bytes c_filename = filename.encode('utf-8')
+    cdef SDL_Surface *image = IMG_Load(c_filename)
+    if image == NULL:
+        return
+    try:
+        return load_from_surface(image)
+    finally:
+        if image:
+            SDL_FreeSurface(image)
+
+def load_from_memory(bytes data):
+    cdef SDL_RWops *rw = NULL
+    cdef SDL_Surface *image = NULL
+    cdef char *c_data = data
+
+    rw = SDL_RWFromMem(c_data, len(data))
+    if rw == NULL:
+        return
+
+    image = IMG_Load_RW(rw, 0)
+    if image == NULL:
+        return
+
+    try:
+        return load_from_surface(image)
+    finally:
+        if image:
+            SDL_FreeSurface(image)
+        if rw:
+            SDL_FreeRW(rw)

kivy/core/image/img_sdl2.py

@@ -27,8 +27,16 @@ class ImageLoaderSDL2(ImageLoaderBase):
     def can_save():
         return True
 
+    @staticmethod
+    def can_load_memory():
+        return True
+
     def load(self, filename):
-        info = _img_sdl2.load(filename)
+        if self._inline:
+            data = filename.read()
+            info = _img_sdl2.load_from_memory(data)
+        else:
+            info = _img_sdl2.load_from_filename(filename)
         if not info:
             Logger.warning('Image: Unable to load image <%s>' % filename)
             raise Exception('SDL2: Unable to load image')
@@ -36,6 +44,7 @@ class ImageLoaderSDL2(ImageLoaderBase):
         w, h, fmt, pixels, rowlength = info
 
         # update internals
+        if not self._inline:
             self.filename = filename
         return [ImageData(
             w, h, fmt, pixels, source=filename,