tdf#134288 svx: fix rendering of text on a zero-width shape

We have conflicting requirements here: on one hand, the shape is zero
width, so the text area is also zero.  On the other hand, we put some
text on the shape, which should be visible.

The result was that the left/right text margin (2x250 mm100) was counted
as part of the text area, so we put a few (but not 1) characters / line
for zero width. Fix this to be PowerPoint-compatible: as the width
decreases, we break the text up to more and more lines, but if the width
is 0, then we don't break it up at all.

An alternative would be to do this later in
SdrTextObj::impDecomposeBlockTextPrimitive(), but there we no longer
know the width is really 0, because the text margins and some small
increase (+1 to be an inclusive range, +1 to have a non-zero scale) is
already added to the original width.

(cherry picked from commit 65e2ef43f186164729e1cc071b805bc1a7125cfe)

Conflicts:
svx/qa/unit/sdr.cxx

Change-Id: Ieaa3e726bc5d37983b6221452e14f01db315f790
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/108873
Tested-by: Jenkins CollaboraOffice <jenkinscollaboraoffice@gmail.com>
Reviewed-by: Miklos Vajna <vmiklos@collabora.com>

3 files changed, 66 insertions, 13 deletions

diff --git a/svx/qa/unit/data/0-width-text-wrap.pptx b/svx/qa/unit/data/0-width-text-wrap.pptx
new file mode 100644
index 000000000000..17349924d89b
--- /dev/null
+++ b/svx/qa/unit/data/0-width-text-wrap.pptx
diff --git a/svx/qa/unit/sdr.cxx b/svx/qa/unit/sdr.cxx
index 093264549db7..f9a61c4962ad 100644
--- a/svx/qa/unit/sdr.cxx
+++ b/svx/qa/unit/sdr.cxx
@@ -53,19 +53,14 @@ public:
         test::BootstrapFixture::tearDown();
     }
     uno::Reference<lang::XComponent>& getComponent() { return mxComponent; }
+
+    drawinglayer::primitive2d::Primitive2DContainer
+    renderPageToPrimitives(const uno::Reference<drawing::XDrawPage>& xDrawPage);
 };
 
-CPPUNIT_TEST_FIXTURE(SdrTest, testShadowScaleOrigin)
+drawinglayer::primitive2d::Primitive2DContainer
+SdrTest::renderPageToPrimitives(const uno::Reference<drawing::XDrawPage>& xDrawPage)
 {
-    // Load a document containing a custom shape.
-    test::Directories aDirectories;
-    OUString aURL = aDirectories.getURLFromSrc("svx/qa/unit/data/shadow-scale-origin.pptx");
-    getComponent() = loadFromDesktop(aURL);
-    uno::Reference<drawing::XDrawPagesSupplier> xDrawPagesSupplier(getComponent(), uno::UNO_QUERY);
-    uno::Reference<drawing::XDrawPage> xDrawPage(xDrawPagesSupplier->getDrawPages()->getByIndex(0),
-                                                 uno::UNO_QUERY);
-
-    // Render it.
     auto pDrawPage = dynamic_cast<SvxDrawPage*>(xDrawPage.get());
     CPPUNIT_ASSERT(pDrawPage);
     SdrPage* pSdrPage = pDrawPage->GetSdrPage();
@@ -75,8 +70,20 @@ CPPUNIT_TEST_FIXTURE(SdrTest, testShadowScaleOrigin)
     const sdr::contact::ViewObjectContact& rDrawPageVOContact
         = pSdrPage->GetViewContact().GetViewObjectContact(aObjectContact);
     sdr::contact::DisplayInfo aDisplayInfo;
+    return rDrawPageVOContact.getPrimitive2DSequenceHierarchy(aDisplayInfo);
+}
+
+CPPUNIT_TEST_FIXTURE(SdrTest, testShadowScaleOrigin)
+{
+    // Load a document containing a custom shape.
+    test::Directories aDirectories;
+    OUString aURL = aDirectories.getURLFromSrc("svx/qa/unit/data/shadow-scale-origin.pptx");
+    getComponent() = loadFromDesktop(aURL);
+    uno::Reference<drawing::XDrawPagesSupplier> xDrawPagesSupplier(getComponent(), uno::UNO_QUERY);
+    uno::Reference<drawing::XDrawPage> xDrawPage(xDrawPagesSupplier->getDrawPages()->getByIndex(0),
+                                                 uno::UNO_QUERY);
     drawinglayer::primitive2d::Primitive2DContainer xPrimitiveSequence
-        = rDrawPageVOContact.getPrimitive2DSequenceHierarchy(aDisplayInfo);
+        = renderPageToPrimitives(xDrawPage);
 
     // Examine the created primitives.
     drawinglayer::tools::Primitive2dXmlDump aDumper;
@@ -91,6 +98,28 @@ CPPUNIT_TEST_FIXTURE(SdrTest, testShadowScaleOrigin)
     CPPUNIT_ASSERT_EQUAL(-705., std::round(fShadowX));
     CPPUNIT_ASSERT_EQUAL(-685., std::round(fShadowY));
 }
+
+CPPUNIT_TEST_FIXTURE(SdrTest, testZeroWidthTextWrap)
+{
+    // Load a document containing a 0-width shape with text.
+    test::Directories aDirectories;
+    OUString aURL = aDirectories.getURLFromSrc("svx/qa/unit/data/0-width-text-wrap.pptx");
+    getComponent() = loadFromDesktop(aURL);
+    uno::Reference<drawing::XDrawPagesSupplier> xDrawPagesSupplier(getComponent(), uno::UNO_QUERY);
+    uno::Reference<drawing::XDrawPage> xDrawPage(xDrawPagesSupplier->getDrawPages()->getByIndex(0),
+                                                 uno::UNO_QUERY);
+    drawinglayer::primitive2d::Primitive2DContainer xPrimitiveSequence
+        = renderPageToPrimitives(xDrawPage);
+
+    // Examine the created primitives.
+    drawinglayer::tools::Primitive2dXmlDump aDumper;
+    xmlDocPtr pDocument = aDumper.dumpAndParse(xPrimitiveSequence);
+    // Without the accompanying fix in place, this test would have failed with:
+    // - Expected: 1
+    // - Actual  : 12
+    // i.e. the text on the only shape on the slide had 12 lines, not a single one.
+    assertXPath(pDocument, "//textsimpleportion", 1);
+}
 }
 
 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/svx/source/sdr/primitive2d/sdrdecompositiontools.cxx b/svx/source/sdr/primitive2d/sdrdecompositiontools.cxx
index 1112230b78ba..228d2f2357b3 100644
--- a/svx/source/sdr/primitive2d/sdrdecompositiontools.cxx
+++ b/svx/source/sdr/primitive2d/sdrdecompositiontools.cxx
@@ -275,12 +275,36 @@ namespace drawinglayer
 
                 // create a range describing the wanted text position and size (aTextAnchorRange). This
                 // means to use the text distance values here
-                const basegfx::B2DPoint aTopLeft(aSnapRange.getMinX() + rText.getTextLeftDistance(), aSnapRange.getMinY() + rText.getTextUpperDistance());
-                const basegfx::B2DPoint aBottomRight(aSnapRange.getMaxX() - rText.getTextRightDistance(), aSnapRange.getMaxY() - rText.getTextLowerDistance());
+                sal_Int32 nTextLeftDistance = rText.getTextLeftDistance();
+                // If the margin is larger than the entire width of the text area, then limit the
+                // margin.
+                if (nTextLeftDistance > aSnapRange.getWidth())
+                    nTextLeftDistance = aSnapRange.getWidth();
+                sal_Int32 nTextRightDistance = rText.getTextRightDistance();
+                if (nTextRightDistance > aSnapRange.getWidth())
+                    nTextRightDistance = aSnapRange.getWidth();
+                const basegfx::B2DPoint aTopLeft(aSnapRange.getMinX() + nTextLeftDistance,
+                                                 aSnapRange.getMinY()
+                                                     + rText.getTextUpperDistance());
+                const basegfx::B2DPoint aBottomRight(aSnapRange.getMaxX() - nTextRightDistance,
+                                                     aSnapRange.getMaxY()
+                                                         - rText.getTextLowerDistance());
                 basegfx::B2DRange aTextAnchorRange;
                 aTextAnchorRange.expand(aTopLeft);
                 aTextAnchorRange.expand(aBottomRight);
 
+                if (aTextAnchorRange.getWidth() == 0)
+                {
+                    // If the shape has no width, then don't attempt to break the text into multiple
+                    // lines, not a single character would satisfy a zero width requirement.
+                    // SdrTextObj::impDecomposeBlockTextPrimitive() uses the same constant to
+                    // effectively set no limits.
+                    aTextAnchorRange.expand(
+                        basegfx::B2DPoint(aTopLeft.getX() - 1000000, aTopLeft.getY()));
+                    aTextAnchorRange.expand(
+                        basegfx::B2DPoint(aBottomRight.getX() + 1000000, aBottomRight.getY()));
+                }
+
                 // now create a transformation from this basic range (aTextAnchorRange)
                 // #i121494# if we have no scale use at least 1.0 to have a carrier e.g. for
                 // mirror values, else these will get lost