Changeset 267 for trunk/src/gui/image/qpixmap_pm.cpp

Timestamp:

Oct 29, 2009, 10:11:44 PM (16 years ago)

Author:

Dmitry A. Kuminov

Message:

gui: Only supply one icon when creating a HPOINTER (WinCreatePointerIndirect() ignores the other one anyway) and make sure that the mini icon is used for HPOINTERs sent to the system tray which expects only mini icons.

File:

• trunk/src/gui/image/qpixmap_pm.cpp (modified) (11 diffs)

trunk/src/gui/image/qpixmap_pm.cpp

@@ -102 +102 @@
     icons and pointers (\sa toPmHPOINTER()).
 
-    Note that if the pixmap does neither have a maks nor the alpha channel but
+    if \a embedRealAlpha is \c true, the real alpha chennel (not the 1bpp mask)
+    will be embedded in the high 8 bits of the 32-bit pixel value for each pixel
+    in the created bitmap (which always has 1 plane and the 32-bit depth). This
+    extra information isn't touched by PM/GPI but may be used by custom drawing
+    routines to do real alpha blending.
+
+    Note that if the pixmap does neither have a mask nor the alpha channel but
     \a mask is not NULL, a NULLHANDLE value will be stored there.
 
@@ -110 +116 @@
     \warning This function is only available on OS/2.
 */
-HBITMAP QPixmap::toPmHBITMAP(HBITMAP *mask) const
+HBITMAP QPixmap::toPmHBITMAP(HBITMAP *mask) const
 {
     if (data->classId() != QPixmapData::RasterClass) {
@@ -130 +136 @@
     HBITMAP hbmMask = NULLHANDLE;
 
-    QImage image = d->image.convertToFormat(QImage::Format_ARGB32).mirrored();
+    // Note that we always use ARGB32 even if embedRealAlpha is false because
+    // in this case we will use the alpha channel to dither the 1bpp mask
+    QImage image = d->image.convertToFormat(QImage::Format_ARGB32);
+    // flip the bitmap top to bottom for PM
+    image = image.mirrored();
 
     // bitmap header + 2 palette entries (for the mask)
@@ -148 +158 @@
 
     if (mask && hasAlpha()) {
-        // get the mask. We prefer QImage::createAlphaMask() over QPixmap::mask()
-        // since the former will dither while the latter will convert any
-        // non-zero alpha value to an opaque pixel
-#if 1
-        QImage mask = image.createAlphaMask().convertToFormat(QImage::Format_Mono);
-
-        // note: for some strange reason, createAlphaMask() (as opposed to
-        // mask().toImage()) returns an image already flipped top to bottom,
-        // so take it into account
-
-        // create the AND mask
-        mask.invertPixels();
-        // add the XOR mask (and leave it zeroed)
-        mask = mask.copy(0, -h, w, h * 2);
-
-#else
-        QImage mask = this->mask().toImage().convertToFormat(QImage::Format_Mono);
-
-        // create the AND mask
-        mask.invertPixels();
-        // add the XOR mask (and leave it zeroed)
-        mask = mask.copy(0, 0, w, h * 2);
-        // flip the bitmap top to bottom for PM
-        mask = mask.mirrored(false, true);
-#endif
+        // get the mask
+        QImage mask;
+        if (!embedRealAlpha) {
+            // We prefer QImage::createAlphaMask() over QPixmap::mask()
+            // since the former will dither while the latter will convert any
+            // non-zero alpha value to an opaque pixel
+            mask = image.createAlphaMask().convertToFormat(QImage::Format_Mono);
+
+            // note: for some strange reason, createAlphaMask() (as opposed to
+            // mask().toImage()) returns an image already flipped top to bottom,
+            // so take it into account
+
+            // create the AND mask
+            mask.invertPixels();
+            // add the XOR mask (and leave it zeroed)
+            mask = mask.copy(0, -h, w, h * 2);
+        } else {
+            // if we embedded real alpha, we still need a mask if we are going
+            // to create a pointer out of this pixmap (WinCreatePointerIndirect()
+            // requirement), but we will use QPixmap::mask() because it won't be
+            // able to destroy the alpha channel of non-fully transparent pixels
+            // when preparing the color bitmap for masking later. We could also
+            // skip this prepare step, but well, let's go this way, it won't hurt.
+            mask = this->mask().toImage().convertToFormat(QImage::Format_Mono);
+
+            // create the AND mask
+            mask.invertPixels();
+            // add the XOR mask (and leave it zeroed)
+            mask = mask.copy(0, 0, w, h * 2);
+            // flip the bitmap top to bottom for PM
+            mask = mask.mirrored(false, true);
+        }
 
         // create the mask bitmap
@@ -192 +209 @@
         POINTL ptls[] = {
             { 0, 0 }, { w - 1, h - 1 },     // dst: inclusive-inclusive
-            { 0, h }, { w, h * 2 },             // src: inclusive-exclusive
+            { 0, h }, { w, h * 2 },         // src: inclusive-exclusive
         };
         ptls[0].y -= h;
@@ -217 +234 @@
     If \a isPointer is \c true, an icon size closest to the system pointer size
     is chosen, otherwise to the system icon size. \a hotX and \a hotY define the
-    hot spot.
+    hot spot. Note is that the size of the resulting pointer will exactly match
+    the system size no matter what size the matched icon is. Smaller icons will
+    be centered in a box corresponding to the system size, larger icons will
+    be scaled down.
+
+    If \a embedRealAlpha is \c true, the color bitmap in the pointer will have
+    the alpha channel embedded in it (see toPmHBITMAP() for details).
+
+    Note that due to the bug in WinCreatePointerIndirect(), hbmMiniPointer and
+    hbmMiniColor field of the POINTERINFO structure are always ignored. For this
+    reason, the caller must choose what icon size (normal or half-size) he wants
+    to get using the \a isMini argument. A bitmap of the respective size will be
+    created and assigned to the hbmColor field.
 
     It is the caller's responsibility to free the \c HPOINTER data
@@ -226 +255 @@
 // static
 HPOINTER QPixmap::toPmHPOINTER(const QIcon &icon, bool isPointer,
-                               int hotX, int hotY)
+                               int hotX, int hotY, bool embedRealAlpha,
+                               bool isMini)
 {
     if (icon.isNull())
@@ -234 +264 @@
     int w = WinQuerySysValue(HWND_DESKTOP, isPointer ? SV_CXPOINTER : SV_CXICON);
     int h = WinQuerySysValue(HWND_DESKTOP, isPointer ? SV_CYPOINTER : SV_CYICON);
-    int w2 = w / 2;
-    int h2 = h / 2;
-
-    // obtain the closest (but never larger) icon sizes we have
+    if (isMini) {
+        w = w / 2;
+        h = h / 2;
+    }
+
+    // obtain the closest (but never larger) icon size we have
     QSize size = icon.actualSize(QSize(w, h));
-    QSize sizeMini = icon.actualSize(QSize(w2, h2));
 
     QPixmap pm = icon.pixmap(size);
-    QPixmap pmMini = icon.pixmap(sizeMini);
-    if (pm.isNull() && pmMini.isNull())
-        return NULLHANDLE;
-
-    // if we got smaller pixmaps then center them inside the system sized rect
-    // instead of letting WinCreatePointerIndirect() scale them (this covers a
-    // usual case when we got 32 and 16 px pixmaps on a 120 DPI system where the
-    // icon size is 40 and 20 px respectively): scaling such small images looks
-    // really ugly.
+    if (pm.isNull())
+        return NULLHANDLE;
+
+    // if we got a smaller pixmap then center it inside the box matching the
+    // system size instead of letting WinCreatePointerIndirect() scale (this
+    // covers a usual case when we get 32/16 px pixmaps on a 120 DPI system
+    // where the icon size is 40/20 px respectively): scaling such small images
+    // looks really ugly.
     if (!pm.isNull() && (pm.width() < w || pm.height() < h)) {
         Q_ASSERT(pm.width() <= w && pm.height() <= h);
@@ -259 +289 @@
         pm = pmNew;
     }
-    if (!pmMini.isNull() && (pmMini.width() < w2 || pmMini.height() < h2)) {
-        Q_ASSERT(pmMini.width() <= w2 && pmMini.height() <= h2);
-        QPixmap pmNew(w2, h2);
-        pmNew.fill(Qt::transparent);
-        QPainter painter(&pmNew);
-        painter.drawPixmap((w2 - pmMini.width()) / 2, (h2 - pmMini.height()) / 2, pmMini);
-        pmMini = pmNew;
-    }
-
-    if (pm.isNull()) {
-        // if we only have the mini icon, use it as a normal one;
-        // WinCreatePointerIndirect() will figure that and not scale it
-        pm = pmMini;
-        pmMini = QPixmap();
-    }
 
     POINTERINFO info;
@@ -279 +294 @@
     info.xHotspot = hotX;
     info.yHotspot = hotY;
-    info.hbmColor = pm.toPmHBITMAP(&info.hbmPointer);
-    if (!pmMini.isNull()) {
-        info.hbmMiniColor = pmMini.toPmHBITMAP(&info.hbmMiniPointer);
-    } else {
-        info.hbmMiniPointer = NULLHANDLE;
-        info.hbmMiniColor = NULLHANDLE;
-    }
+    info.hbmColor = pm.toPmHBITMAP(&info.hbmPointer, embedRealAlpha);
+    info.hbmMiniPointer = NULLHANDLE;
+    info.hbmMiniColor = NULLHANDLE;
 
     HPOINTER hIcon = WinCreatePointerIndirect(HWND_DESKTOP, &info);
@@ -291 +302 @@
     GpiDeleteBitmap(info.hbmPointer);
     GpiDeleteBitmap(info.hbmColor);
-    GpiDeleteBitmap(info.hbmMiniPointer);
-    GpiDeleteBitmap(info.hbmMiniColor);
 
     return hIcon;