+//---------------------------------------------------------------------------
+// Factory functions for creating wxBitmaps from Python buffer objects. They
+// use the Abstract Pixel API to be able to set RGB and A bytes directly into
+// the wxBitmap's pixel buffer.
+
+%{
+// See http://tinyurl.com/e5adr for what premultiplying alpha means. It
+// appears to me that the other platforms are already doing it, so I'll just
+// automatically do it for wxMSW here.
+#ifdef __WXMSW__
+#define wxPy_premultiply(p, a) ((p) * (a) / 256)
+#else
+#define wxPy_premultiply(p, a) (p)
+#endif
+%}
+
+
+%newobject _BitmapFromBufferAlpha;
+%newobject _BitmapFromBuffer;
+%inline %{
+ wxBitmap* _BitmapFromBufferAlpha(int width, int height,
+ buffer data, int DATASIZE,
+ buffer alpha, int ALPHASIZE)
+ {
+ if (DATASIZE != width*height*3) {
+ wxPyErr_SetString(PyExc_ValueError, "Invalid data buffer size.");
+ return NULL;
+ }
+
+ if (ALPHASIZE != width*height) {
+ wxPyErr_SetString(PyExc_ValueError, "Invalid alpha buffer size.");
+ return NULL;
+ }
+
+ wxBitmap* bmp = new wxBitmap(width, height, 32);
+ wxAlphaPixelData pixels(*bmp, wxPoint(0,0), wxSize(width,height));
+ if (! pixels) {
+ // raise an exception...
+ wxPyErr_SetString(PyExc_RuntimeError,
+ "Failed to gain raw access to bitmap data.");
+ return NULL;
+ }
+
+ pixels.UseAlpha();
+ wxAlphaPixelData::Iterator p(pixels);
+ for (int y=0; y<height; y++) {
+ wxAlphaPixelData::Iterator rowStart = p;
+ for (int x=0; x<width; x++) {
+ byte a = *(alpha++);
+ p.Red() = wxPy_premultiply(*(data++), a);
+ p.Green() = wxPy_premultiply(*(data++), a);
+ p.Blue() = wxPy_premultiply(*(data++), a);
+ p.Alpha() = a;
+ ++p;
+ }
+ p = rowStart;
+ p.OffsetY(pixels, 1);
+ }
+ return bmp;
+ }
+
+ wxBitmap* _BitmapFromBuffer(int width, int height, buffer data, int DATASIZE)
+ {
+ if (DATASIZE != width*height*3) {
+ wxPyErr_SetString(PyExc_ValueError, "Invalid data buffer size.");
+ return NULL;
+ }
+
+ wxBitmap* bmp = new wxBitmap(width, height, 24);
+ wxNativePixelData pixels(*bmp, wxPoint(0,0), wxSize(width,height));
+ if (! pixels) {
+ // raise an exception...
+ wxPyErr_SetString(PyExc_RuntimeError,
+ "Failed to gain raw access to bitmap data.");
+ return NULL;
+ }
+
+ wxNativePixelData::Iterator p(pixels);
+ for (int y=0; y<height; y++) {
+ wxNativePixelData::Iterator rowStart = p;
+ for (int x=0; x<width; x++) {
+ p.Red() = *(data++);
+ p.Green() = *(data++);
+ p.Blue() = *(data++);
+ ++p;
+ }
+ p = rowStart;
+ p.OffsetY(pixels, 1);
+ }
+ return bmp;
+ }
+%}
+
+
+%pythoncode {
+def BitmapFromBuffer(width, height, dataBuffer, alphaBuffer=None):
+ """
+ Creates a `wx.Bitmap` from the data in dataBuffer. The dataBuffer
+ parameter must be a Python object that implements the buffer interface, or
+ is convertable to a buffer object, such as a string, array, etc. The
+ dataBuffer object is expected to contain a series of RGB bytes and be
+ width*height*3 bytes long. A buffer object can optionally be supplied for
+ the image's alpha channel data, and it is expected to be width*height
+ bytes long. On Windows the RGB values are 'premultiplied' by the alpha
+ values. (The other platforms appear to already be premultiplying the
+ alpha.)
+
+ Unlike `wx.ImageFromBuffer` the bitmap created with this function does not
+ share the memory buffer with the buffer object. This is because the
+ native pixel buffer format varies on different platforms, and so instead
+ an efficient as possible copy of the data is made from the buffer objects
+ to the bitmap's native pixel buffer. For direct access to a bitmap's
+ pixel buffer see `wx.NativePixelData` and `wx.AlphaPixelData`.
+
+ :see: `wx.Bitmap`, `wx.BitmapFromBufferRGBA`, `wx.NativePixelData`,
+ `wx.AlphaPixelData`, `wx.ImageFromBuffer`
+ """
+ if not isinstance(dataBuffer, buffer):
+ dataBuffer = buffer(dataBuffer)
+ if alphaBuffer is not None and not isinstance(alphaBuffer, buffer):
+ alphaBuffer = buffer(alphaBuffer)
+ if alphaBuffer is not None:
+ return _gdi_._BitmapFromBufferAlpha(width, height, dataBuffer, alphaBuffer)
+ else:
+ return _gdi_._BitmapFromBuffer(width, height, dataBuffer)
+}
+
+
+
+%newobject _BitmapFromBufferRGBA;
+%inline %{
+ wxBitmap* _BitmapFromBufferRGBA(int width, int height, buffer data, int DATASIZE)
+ {
+ if (DATASIZE != width*height*4) {
+ wxPyErr_SetString(PyExc_ValueError, "Invalid data buffer size.");
+ return NULL;
+ }
+
+ wxBitmap* bmp = new wxBitmap(width, height, 32);
+ wxAlphaPixelData pixels(*bmp, wxPoint(0,0), wxSize(width,height));
+ if (! pixels) {
+ // raise an exception...
+ wxPyErr_SetString(PyExc_RuntimeError,
+ "Failed to gain raw access to bitmap data.");
+ return NULL;
+ }
+
+ pixels.UseAlpha();
+ wxAlphaPixelData::Iterator p(pixels);
+ for (int y=0; y<height; y++) {
+ wxAlphaPixelData::Iterator rowStart = p;
+ for (int x=0; x<width; x++) {
+ byte a = data[3];
+ p.Red() = wxPy_premultiply(*(data++), a);
+ p.Green() = wxPy_premultiply(*(data++), a);
+ p.Blue() = wxPy_premultiply(*(data++), a);
+ p.Alpha() = a; data++;
+ ++p;
+ }
+ p = rowStart;
+ p.OffsetY(pixels, 1);
+ }
+ return bmp;
+ }
+%}
+
+%pythoncode {
+def BitmapFromBufferRGBA(width, height, dataBuffer):
+ """
+ Creates a `wx.Bitmap` from the data in dataBuffer. The dataBuffer
+ parameter must be a Python object that implements the buffer interface, or
+ is convertable to a buffer object, such as a string, array, etc. The
+ dataBuffer object is expected to contain a series of RGBA bytes (red,
+ green, blue and alpha) and be width*height*4 bytes long. On Windows the
+ RGB values are 'premultiplied' by the alpha values. (The other platforms
+ appear to already be premultiplying the alpha.)
+
+ Unlike `wx.ImageFromBuffer` the bitmap created with this function does not
+ share the memory buffer with the buffer object. This is because the
+ native pixel buffer format varies on different platforms, and so instead
+ an efficient as possible copy of the data is made from the buffer object
+ to the bitmap's native pixel buffer. For direct access to a bitmap's
+ pixel buffer see `wx.NativePixelData` and `wx.AlphaPixelData`.
+
+ :see: `wx.Bitmap`, `wx.BitmapFromBuffer`, `wx.NativePixelData`,
+ `wx.AlphaPixelData`, `wx.ImageFromBuffer`
+ """
+ if not isinstance(dataBuffer, buffer):
+ dataBuffer = buffer(dataBuffer)
+ return _gdi_._BitmapFromBufferRGBA(width, height, dataBuffer)
+}
+
+
projects / wxWidgets.git / blobdiff