diff options
Diffstat (limited to 'generic')
| -rw-r--r-- | generic/tkImgPhoto.c | 48 |
1 files changed, 29 insertions, 19 deletions
diff --git a/generic/tkImgPhoto.c b/generic/tkImgPhoto.c index 86074b6..d3fc6d9 100644 --- a/generic/tkImgPhoto.c +++ b/generic/tkImgPhoto.c @@ -17,7 +17,7 @@ * Department of Computer Science, * Australian National University. * - * RCS: @(#) $Id: tkImgPhoto.c,v 1.64 2006/03/16 10:04:49 das Exp $ + * RCS: @(#) $Id: tkImgPhoto.c,v 1.65 2006/05/13 00:47:20 hobbs Exp $ */ #include "tkInt.h" @@ -4623,25 +4623,30 @@ Tk_PhotoPutBlock( * Check if display code needs alpha blending... */ - if (!sourceIsSimplePhoto || masterPtr->flags & COMPLEX_ALPHA) { + if (!sourceIsSimplePhoto && (width == 1) && (height == 1)) { /* - * Note that we skip in the single pixel case if we can. This speeds - * up code that builds up large simple-alpha images by single pixels, - * which seems to be a common use-case. [Bug 1409140] + * Optimize the single pixel case if we can. This speeds up code that + * builds up large simple-alpha images by single pixels. We don't + * negate COMPLEX_ALPHA in this case. [Bug 1409140] */ - - if (width == 1 && height == 1 && !(masterPtr->flags & COMPLEX_ALPHA)) { + if (!(masterPtr->flags & COMPLEX_ALPHA)) { unsigned char newAlpha; destLinePtr = masterPtr->pix32 + (y * masterPtr->width + x) * 4; newAlpha = destLinePtr[3]; - if (newAlpha > 0 && newAlpha < 255) { + if (newAlpha && newAlpha != 255) { masterPtr->flags |= COMPLEX_ALPHA; } - } else { - ToggleComplexAlphaIfNeeded(masterPtr); } + } else if ((alphaOffset != 0) || (masterPtr->flags & COMPLEX_ALPHA)) { + /* + * Check for partial transparency if alpha pixels are specified, or + * rescan if we already knew such pixels existed. To restrict this + * Toggle to only checking the changed pixels requires knowing where + * the alpha pixels are. + */ + ToggleComplexAlphaIfNeeded(masterPtr); } /* @@ -4921,25 +4926,30 @@ Tk_PhotoPutZoomedBlock( * Check if display code needs alpha blending... */ - if (!sourceIsSimplePhoto || masterPtr->flags & COMPLEX_ALPHA) { + if (!sourceIsSimplePhoto && (width == 1) && (height == 1)) { /* - * Note that we skip in the single pixel case if we can. This speeds - * up code that builds up large simple-alpha images by single pixels, - * which seems to be a common use-case. [Bug 1409140] + * Optimize the single pixel case if we can. This speeds up code that + * builds up large simple-alpha images by single pixels. We don't + * negate COMPLEX_ALPHA in this case. [Bug 1409140] */ - - if (width == 1 && height == 1 && !(masterPtr->flags & COMPLEX_ALPHA)) { + if (!(masterPtr->flags & COMPLEX_ALPHA)) { unsigned char newAlpha; destLinePtr = masterPtr->pix32 + (y * masterPtr->width + x) * 4; newAlpha = destLinePtr[3]; - if (newAlpha > 0 && newAlpha < 255) { + if (newAlpha && newAlpha != 255) { masterPtr->flags |= COMPLEX_ALPHA; } - } else { - ToggleComplexAlphaIfNeeded(masterPtr); } + } else if ((alphaOffset != 0) || (masterPtr->flags & COMPLEX_ALPHA)) { + /* + * Check for partial transparency if alpha pixels are specified, or + * rescan if we already knew such pixels existed. To restrict this + * Toggle to only checking the changed pixels requires knowing where + * the alpha pixels are. + */ + ToggleComplexAlphaIfNeeded(masterPtr); } /* |