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| author | culler <culler> | 2021-05-01 21:37:00 (GMT) |
|---|---|---|
| committer | culler <culler> | 2021-05-01 21:37:00 (GMT) |
| commit | 3c4f9f531b94668f572cf0ca3de704edfcd81055 (patch) | |
| tree | 63eb2ea7ae5dba7ac747d476e2cde3a40edbf16d | |
| parent | 1a692b15205d5c7f4480dfee96ab812ec8bfc800 (diff) | |
| download | tk-3c4f9f531b94668f572cf0ca3de704edfcd81055.zip tk-3c4f9f531b94668f572cf0ca3de704edfcd81055.tar.gz tk-3c4f9f531b94668f572cf0ca3de704edfcd81055.tar.bz2 | |
Edit comments. Use uint32_t since Apple documentation specifies that type for kCGImageAlphaLast etc.
| -rw-r--r-- | macosx/tkMacOSXImage.c | 25 |
1 files changed, 18 insertions, 7 deletions
diff --git a/macosx/tkMacOSXImage.c b/macosx/tkMacOSXImage.c index 85b109d..410e38e 100644 --- a/macosx/tkMacOSXImage.c +++ b/macosx/tkMacOSXImage.c @@ -391,14 +391,25 @@ XCreateImage( /* *---------------------------------------------------------------------- * - * TkPutImage, XPutImage -- - * - * Copies a rectangular subimage of an XImage into a drawable. Currently - * this is only called by TkImgPhotoDisplay, using a Window as the - * drawable. + * TkPutImage, XPutImage, TkpPutRGBAImage -- + * + * These functions, which all have the same signature, copy a rectangular + * subimage of an XImage into a drawable. The first two are identical on + * macOS. They assume that the XImage data has the structure of a 32bpp + * ZPixmap in which the image data is an array of 32bit integers packed + * with 8 bit values for the Red Green and Blue channels. They ignore the + * fourth byte. The function TkpPutRGBAImage assumes that the XImage data + * has been extended by using the fourth byte to store an 8-bit Alpha + * value. (The Alpha data is assumed not to pre-multiplied). The image + * is then drawn into the drawable using standard Porter-Duff Source Atop + * Composition (kCGBlendModeSourceAtop in Apple's Core Graphics). + * + * The TkpPutRGBAfunction is used by TkImgPhotoDisplay to render photo + * images if the compile-time variable TK_CAN_RENDER_RGBA is defined in + * a platform's tkXXXXPort.h header, as is the case for the macOS Aqua port. * * Results: - * None. + * These functions always return Success. * * Side effects: * Draws the image on the specified drawable. @@ -413,7 +424,7 @@ XCreateImage( static int TkMacOSXPutImage( - uint32 pixelFormat, + uint32_t pixelFormat, Display* display, /* Display. */ Drawable drawable, /* Drawable to place image on. */ GC gc, /* GC to use. */ |