Ticket #12057: 608-improvements-1.patch

mythtv/libs/libmythtv/subtitlescreen.cpp

@@ -335 +335 @@
     result->SetOutline(outline, color, off, alpha);
 
     LOG(VB_VBI, LOG_DEBUG,
-        QString("GetFont(family=%1, prefix=%2, orig pixelSize=%3, "
-                "new pixelSize=%4 zoom=%5) = %6")
-        .arg(family).arg(prefix).arg(origPixelSize).arg(pixelSize)
-        .arg(zoom).arg(fontToString(result)));
+        QString("GetFont(family=%1 prefix=%2 orig pixelSize=%3 zoom=%4 stretch=%5) = %6")
+        .arg(family).arg(prefix).arg(origPixelSize)
+        .arg(zoom).arg(stretch).arg(fontToString(result)));
     return result;
 }
 
@@ -690 +689 @@
     int leftPadding, rightPadding;
     CalcPadding(isFirst, isLast, leftPadding, rightPadding);
     // Account for extra padding before the first chunk.
-    if (isFirst)
-        x += leftPadding;
+    // No, this will cause everything to be off center to the right
+    // by the value of leftPadding.
+    // if (isFirst)
+    //     x += leftPadding;
     QSize chunk_sz = CalcSize();
     QRect bgrect(x - leftPadding, y,
                  chunk_sz.width() + leftPadding + rightPadding,
@@ -909 +910 @@
             // order of the children.  In particular, background
             // shapes should be added/drawn first, and text drawn on
             // top.
+            LOG(VB_VBI, LOG_DEBUG,
+                QString("i=%1 rect=%2x%3@%4,%5 bgrect=%6x%7@%8,%9 text=%10")
+                .arg(i)
+                .arg(chunk->textRect.width())
+                .arg(chunk->textRect.height())
+                .arg(chunk->textRect.x())
+                .arg(chunk->textRect.y())
+                .arg(chunk->bgShapeRect.width())
+                .arg(chunk->bgShapeRect.height())
+                .arg(chunk->bgShapeRect.x())
+                .arg(chunk->bgShapeRect.y())
+                .arg(chunk->text));
             SubSimpleText *text =
                 new SubSimpleText((*chunk).text, *mythfont,
                                   (*chunk).textRect,
@@ -1233 +1246 @@
             m_lines[i].y_indent = prevY + spaceBefore[i] * shrink;
             prevY = m_lines[i].y_indent + heights[i];
         }
+        LOG(VB_VBI, LOG_DEBUG,
+            QString("Shrink overage=%1 totalSpace=%2 shrink=%3 firstY=%4 prevY=%5")
+            .arg(overage).arg(totalSpace).arg(shrink).arg(firstY).arg(prevY));
     }
 
     // Shift Y coordinates back up into the safe area.
@@ -1254 +1270 @@
     if (buffers.empty())
         return;
     vector<CC608Text*>::const_iterator i = buffers.begin();
-    int xscale = 36;
-    int yscale = 17;
-    int pixelSize = m_safeArea.height() / (yscale * LINE_SPACING);
+
+    int xscale = 32;    // 608 max columns
+    int yscale = 15;    // 608 max rows
+
+    // Set pixelSize to the target lineHeight
+    // It is a first guess pixelSize, which will almost certainly be off
+    int pixelSize = m_safeArea.height() / yscale;
+    int lineHeight = pixelSize;
     int fontwidth = 0;
     int xmid = 0;
     int zoom = 100;
@@ -1266 +1287 @@
         m_subScreen->SetFontSize(pixelSize);
         CC708CharacterAttribute def_attr(false, false, false, clr[0]);
         QFont *font = m_subScreen->GetFont(def_attr)->GetFace();
+
+        // Set the pixelSize, again, to undo scaling done by
+        // SubtitleScreen::GetFont().
+        // It will be scaled appropriately after we establish
+        // a baseline pixelSize for 100% zoom.
+        font->setPixelSize(pixelSize);
+
         QFontMetrics fm(*font);
+        // Font metrics for various fonts are inconsistent in how
+        // they provide a realistic line height value.
+        // The max of what they call height and lineSpacing
+        // provides a resonable value for most fonts.
+        lineHeight = max(fm.height(), fm.lineSpacing());
+
+        int offBy = lineHeight - pixelSize;
+        int newPixelSize = pixelSize;
+        int newLineHeight = lineHeight;
+        if (offBy != 0)
+        {
+            // We tried a pixelSize equal to the desired font height,
+            // but it didn't quite get us there.
+            // We make a better guess by applying a ratio of
+            // our first guess divided by the actual height.
+            // This should be "good enough" for most fonts.
+            newPixelSize = pixelSize * pixelSize / lineHeight;
+            m_subScreen->SetFontSize(newPixelSize);
+            font = m_subScreen->GetFont(def_attr)->GetFace();
+            font->setPixelSize(newPixelSize);
+            fm = QFontMetrics(*font);
+            newLineHeight = max(fm.height(), fm.lineSpacing());
+        }
         fontwidth = fm.averageCharWidth();
+        LOG(VB_VBI, LOG_DEBUG,
+            QString("Unscaled pixelSize=%1->%2 lineHeight=%3->%4 fontwidth=%5 offBy=%6 zoom=%7")
+            .arg(pixelSize).arg(newPixelSize).arg(lineHeight).arg(newLineHeight)
+            .arg(fontwidth).arg(offBy).arg(zoom));
+        lineHeight = newLineHeight;
+
+        // Now that we have our baseline,
+        // we can apply the zoom factor.
+        if (zoom != 100)
+        {
+            font = m_subScreen->GetFont(def_attr)->GetFace();
+            fm = QFontMetrics(*font);
+            fontwidth = fm.averageCharWidth();
+            lineHeight = max(fm.height(), fm.lineSpacing());
+            LOG(VB_VBI, LOG_DEBUG,
+                QString("Scaled lineHeight=%1 fontwidth=%2")
+                .arg(lineHeight).arg(fontwidth));
+        }
         xmid = m_safeArea.width() / 2;
         // Disable centering for zoom factor >= 100%
-        if (zoom >= 100)
-            xscale = m_safeArea.width() / fontwidth;
+        // Why?? If disabled, 608 captions are shifted to left unless
+        // the user sets the zoom to 99% or less.
+        // The Layout method should shift left-right and up-down
+        // as needed for zoom factor.
+        // If zoom factor is too large, the user can reduce it.
+        //if (zoom >= 100)
+        //    xscale = m_safeArea.width() / fontwidth;
     }
 
     for (; i != buffers.end(); ++i)
@@ -1282 +1356 @@
         const bool isBold = false;
         QString text(cc->text);
 
+        // Note: cc-x (and orig_x) is column # ranging from 0 through 31,
         int orig_x = cc->x;
         // position as if we use a fixed size font
         // - font size already has zoom factor applied
@@ -1294 +1369 @@
             // fallback
             x = (orig_x + 3) * m_safeArea.width() / xscale;
 
+        // Note: cc-y (and orig_y) is row # ranging from 1 through 15,
+        // we need zero based rows
         int orig_y = cc->y;
         int y;
-        if (orig_y < yscale / 2)
+        if (orig_y <= yscale / 2)
             // top half -- anchor up
-            y = (orig_y * m_safeArea.height() * zoom / (yscale * 100));
+            y = (orig_y-1) * lineHeight;
         else
             // bottom half -- anchor down
-            y = m_safeArea.height() -
-                ((yscale - orig_y - 0.5) * m_safeArea.height() * zoom /
-                 (yscale * 100));
+            y = m_safeArea.height() - ((yscale - (orig_y-1)) * lineHeight);
 
         FormattedTextLine line(x, y, orig_x, orig_y);
         while (!text.isNull())
@@ -1661 +1736 @@
     QFont *font = mythfont->GetFace();
     QFontMetrics fm(*font);
     int width = fm.width(text);
-    int height = fm.height() * (1 + PAD_HEIGHT);
+
+    // Font metrics for various fonts are inconsistent in how
+    // they provide a realistic line height value.
+    // The max of what they call height and lineSpacing
+    // provides a resonable value for most fonts.
+    int height = max(fm.height(), fm.lineSpacing());
+
     if (layoutSpacing > 0 && !text.trimmed().isEmpty())
         height = max(height, (int)(font->pixelSize() * layoutSpacing));
     height += CalcShadowOffsetPadding(mythfont).height();
@@ -1813 +1894 @@
         return;
 
     QRect bounding  = visible.boundingRect();
+    LOG(VB_VBI, LOG_DEBUG,
+        QString("Visible bounds=%1x%2@%3,%4")
+        .arg(bounding.width()).arg(bounding.height())
+        .arg(bounding.x()).arg(bounding.y()));
+
     bounding = bounding.translated(m_safeArea.topLeft());
+    LOG(VB_VBI, LOG_DEBUG,
+        QString("Translated bounds=%1x%2@%3,%4")
+        .arg(bounding.width()).arg(bounding.height())
+        .arg(bounding.x()).arg(bounding.y()));
+
     bounding = m_safeArea.intersected(bounding);
     int left = m_safeArea.left() - bounding.left();
     int top  = m_safeArea.top()  - bounding.top();
+    LOG(VB_VBI, LOG_DEBUG,
+        QString("Intersected bounds=%1x%2@%3,%4 left=%5 right=%6")
+        .arg(bounding.width()).arg(bounding.height())
+        .arg(bounding.x()).arg(bounding.y())
+        .arg(left).arg(top));
     SetArea(MythRect(bounding));
 
     i.toFront();