Bug 375141 - convert svg text to thebes. r=longsonr, sr=roc

layout/svg/base/src/nsSVGGlyphFrame.cpp

@@ -53,7 +53,12 @@
 #include "nsDOMError.h"
 #include "gfxContext.h"
 #include "gfxMatrix.h"
-#include "cairo.h"
+#include "gfxPlatform.h"
+
+// XXX: This initial straightforward conversion from accessing cairo
+// directly to Thebes doesn't handle clusters.  Pretty much all code
+// that measures or draws single characters (textPath code and some
+// DOM accessors) will need to be reworked.
 
 //----------------------------------------------------------------------
 // Implementation
@@ -117,6 +122,35 @@ nsSVGGlyphFrame::DidSetStyleContext()
 {
   nsSVGGlyphFrameBase::DidSetStyleContext();
 
+  const nsStyleFont* fontData = GetStyleFont();
+  nsFont font = fontData->mFont;
+
+  // Since SVG has its own scaling, we really don't want
+  // fonts in SVG to respond to the browser's "TextZoom"
+  // (Ctrl++,Ctrl+-)
+  nsPresContext *presContext = PresContext();
+  float textZoom = presContext->TextZoom();
+  double size = presContext->AppUnitsToDevPixels(fontData->mSize) / textZoom;
+
+  nsCAutoString langGroup;
+  nsIAtom *langGroupAtom = presContext->GetLangGroup();
+  if (langGroupAtom) {
+    const char* lg;
+    langGroupAtom->GetUTF8String(&lg);
+    langGroup.Assign(lg);
+  }
+
+  // XXX decorations are ignored by gfxFontStyle - still need to implement
+  mFontStyle = new gfxFontStyle(font.style, font.variant,
+                                font.weight, font.decorations,
+                                size, langGroup, font.sizeAdjust,
+                                font.systemFont, font.familyNameQuirks);
+
+  if (mFontStyle) {
+    mFontGroup =
+      gfxPlatform::GetPlatform()->CreateFontGroup(font.name, mFontStyle);
+  }
+
   return UpdateGraphic();
 }
 
@@ -179,23 +213,43 @@ nsSVGGlyphFrame::GetType() const
 // nsISVGChildFrame methods
 
 void
-nsSVGGlyphFrame::LoopCharacters(cairo_t *aCtx, const nsAString &aText,
+nsSVGGlyphFrame::LoopCharacters(gfxContext *aCtx, const nsString &aText,
                                 const nsSVGCharacterPosition *aCP,
-                                void (*aFunc)(cairo_t *cr, const char *utf8))
+                                FillOrStroke aFillOrStroke)
 {
+  nsAutoPtr<gfxTextRun> textRun(GetTextRun(aCtx, aText));
+
+  if (!textRun)
+    return;
+
   if (!aCP) {
-    aFunc(aCtx, NS_ConvertUTF16toUTF8(aText).get());
+    if (aFillOrStroke == STROKE) {
+      textRun->DrawToPath(aCtx, mPosition, 0, aText.Length(), nsnull, nsnull);
+    } else {
+      textRun->Draw(aCtx, mPosition, 0, aText.Length(),
+                    nsnull, nsnull, nsnull);
+    }
   } else {
     for (PRUint32 i = 0; i < aText.Length(); i++) {
       /* character actually on the path? */
       if (aCP[i].draw == PR_FALSE)
         continue;
-      cairo_matrix_t matrix;
-      cairo_get_matrix(aCtx, &matrix);
-      cairo_move_to(aCtx, aCP[i].x, aCP[i].y);
-      cairo_rotate(aCtx, aCP[i].angle);
-      aFunc(aCtx, NS_ConvertUTF16toUTF8(Substring(aText, i, 1)).get());
-      cairo_set_matrix(aCtx, &matrix);
+
+      gfxMatrix matrix = aCtx->CurrentMatrix();
+
+      gfxMatrix rot;
+      rot.Rotate(aCP[i].angle);
+      aCtx->Multiply(rot);
+
+      rot.Invert();
+      gfxPoint pt = rot.Transform(aCP[i].pos);
+
+      if (aFillOrStroke == STROKE) {
+        textRun->DrawToPath(aCtx, pt, i, 1, nsnull, nsnull);
+      } else {
+        textRun->Draw(aCtx, pt, i, 1, nsnull, nsnull, nsnull);
+      }
+      aCtx->SetMatrix(matrix);
     }
   }
 }
@@ -214,70 +268,62 @@ nsSVGGlyphFrame::PaintSVG(nsSVGRenderState *aContext, nsRect *aDirtyRect)
   nsAutoArrayPtr<nsSVGCharacterPosition> cp;
 
   gfxContext *gfx = aContext->GetGfxContext();
-  cairo_t *ctx = gfx->GetCairo();
-
-  SelectFont(gfx);
 
   nsresult rv = GetCharacterPosition(gfx, text, getter_Transfers(cp));
 
-  cairo_matrix_t matrix;
+  gfxMatrix matrix;
 
   PRUint16 renderMode = aContext->GetRenderMode();
 
   if (renderMode == nsSVGRenderState::NORMAL) {
     /* save/pop the state so we don't screw up the xform */
-    cairo_save(ctx);
+    gfx->Save();
   }
   else {
-    cairo_get_matrix(ctx, &matrix);
+    matrix = gfx->CurrentMatrix();
   }
 
   rv = GetGlobalTransform(gfx);
   if (NS_FAILED(rv)) {
     if (renderMode == nsSVGRenderState::NORMAL)
-      cairo_restore(ctx);
+      gfx->Restore();
     return rv;
   }
 
-  if (!cp)
-    cairo_move_to(ctx, mX, mY);
-
   if (renderMode != nsSVGRenderState::NORMAL) {
     if (GetClipRule() == NS_STYLE_FILL_RULE_EVENODD)
-      cairo_set_fill_rule(ctx, CAIRO_FILL_RULE_EVEN_ODD);
+      gfx->SetFillRule(gfxContext::FILL_RULE_EVEN_ODD);
     else
-      cairo_set_fill_rule(ctx, CAIRO_FILL_RULE_WINDING);
+      gfx->SetFillRule(gfxContext::FILL_RULE_WINDING);
 
     if (renderMode == nsSVGRenderState::CLIP_MASK) {
-      cairo_set_antialias(ctx, CAIRO_ANTIALIAS_NONE);
-      cairo_set_source_rgba(ctx, 1.0f, 1.0f, 1.0f, 1.0f);
-      LoopCharacters(ctx, text, cp, cairo_show_text);
+      gfx->SetAntialiasMode(gfxContext::MODE_ALIASED);
+      gfx->SetColor(gfxRGBA(1.0f, 1.0f, 1.0f, 1.0f));
+      LoopCharacters(gfx, text, cp, FILL);
     } else {
-      LoopCharacters(ctx, text, cp, cairo_text_path);
+      LoopCharacters(gfx, text, cp, STROKE);
     }
 
-    cairo_set_matrix(ctx, &matrix);
+    gfx->SetMatrix(matrix);
 
     return NS_OK;
   }
 
   void *closure;
   if (HasFill() && NS_SUCCEEDED(SetupCairoFill(gfx, &closure))) {
-    LoopCharacters(ctx, text, cp, cairo_show_text);
+    LoopCharacters(gfx, text, cp, FILL);
     CleanupCairoFill(gfx, closure);
   }
 
   if (HasStroke() && NS_SUCCEEDED(SetupCairoStroke(gfx, &closure))) {
-    cairo_new_path(ctx);
-    if (!cp)
-      cairo_move_to(ctx, mX, mY);
-    LoopCharacters(ctx, text, cp, cairo_text_path);
-    cairo_stroke(ctx);
+    gfx->NewPath();
+    LoopCharacters(gfx, text, cp, STROKE);
+    gfx->Stroke();
     CleanupCairoStroke(gfx, closure);
-    cairo_new_path(ctx);
+    gfx->NewPath();
   }
 
-  cairo_restore(ctx);
+  gfx->Restore();
 
   return NS_OK;
 }
@@ -362,60 +408,64 @@ nsSVGGlyphFrame::UpdateCoveredRegion()
 
   nsSVGAutoGlyphHelperContext ctx(this, text, getter_Transfers(cp));
 
-  nsresult rv = GetGlobalTransform(ctx);
+  gfxContext *gfx = ctx.GetContext();
+  gfxTextRun *textRun = ctx.GetTextRun();
+  if (!gfx || !textRun)
+    return NS_ERROR_OUT_OF_MEMORY;
+
+  nsresult rv = GetGlobalTransform(gfx);
   NS_ENSURE_SUCCESS(rv, rv);
 
   if (!cp) {
-    cairo_move_to(ctx, mX, mY);
-
     if (hasStroke) {
-      cairo_text_path(ctx, NS_ConvertUTF16toUTF8(text).get());
+      textRun->DrawToPath(gfx, mPosition, 0, text.Length(), nsnull, nsnull);
     } else {
-      cairo_text_extents_t extent;
-      cairo_text_extents(ctx,
-                         NS_ConvertUTF16toUTF8(text).get(),
-                         &extent);
-      cairo_rectangle(ctx, mX + extent.x_bearing, mY + extent.y_bearing,
-                      extent.width, extent.height);
+      gfxTextRun::Metrics metrics =
+        textRun->MeasureText(0, text.Length(), PR_FALSE, nsnull);
+      gfx->Rectangle(metrics.mBoundingBox + mPosition);
     }
   } else {
-    cairo_matrix_t matrix;
     for (PRUint32 i=0; i<text.Length(); i++) {
       /* character actually on the path? */
       if (cp[i].draw == PR_FALSE)
         continue;
-      cairo_get_matrix(ctx, &matrix);
-      cairo_move_to(ctx, cp[i].x, cp[i].y);
-      cairo_rotate(ctx, cp[i].angle);
-      if (hasStroke) {
-        cairo_text_path(ctx, NS_ConvertUTF16toUTF8(Substring(text, i, 1)).get());
-      } else {
-        cairo_text_extents_t extent;
-        cairo_text_extents(ctx,
-                           NS_ConvertUTF16toUTF8(Substring(text, i, 1)).get(),
-                           &extent);
-        cairo_rel_move_to(ctx, extent.x_bearing, extent.y_bearing);
-        cairo_rel_line_to(ctx, extent.width, 0);
-        cairo_rel_line_to(ctx, 0, extent.height);
-        cairo_rel_line_to(ctx, -extent.width, 0);
-        cairo_close_path(ctx);
-      }
-      cairo_set_matrix(ctx, &matrix);
-    }
-  }
 
-  double xmin, ymin, xmax, ymax;
+      gfxMatrix matrix = gfx->CurrentMatrix();
 
       if (hasStroke) {
-    SetupCairoStrokeGeometry(ctx);
-    cairo_stroke_extents(ctx, &xmin, &ymin, &xmax, &ymax);
-    nsSVGUtils::UserToDeviceBBox(ctx, &xmin, &ymin, &xmax, &ymax);
+        gfxMatrix rot;
+        rot.Rotate(cp[i].angle);
+        gfx->Multiply(rot);
+
+        rot.Invert();
+        gfxPoint pt = rot.Transform(cp[i].pos);
+
+        textRun->DrawToPath(gfx, pt, i, 1, nsnull, nsnull);
       } else {
-    cairo_identity_matrix(ctx);
-    cairo_fill_extents(ctx, &xmin, &ymin, &xmax, &ymax);
+        gfx->MoveTo(cp[i].pos);
+        gfx->Rotate(cp[i].angle);
+
+        gfxTextRun::Metrics metrics =
+          textRun->MeasureText(i, 1, PR_FALSE, nsnull);
+
+        gfx->Rectangle(metrics.mBoundingBox + gfx->CurrentPoint());
+      }
+      gfx->SetMatrix(matrix);
+    }
   }
 
-  mRect = nsSVGUtils::ToBoundingPixelRect(xmin, ymin, xmax, ymax);
+  gfxRect extent;
+
+  if (hasStroke) {
+    SetupCairoStrokeGeometry(gfx);
+    extent = gfx->GetUserStrokeExtent();
+    extent = gfx->UserToDevice(extent);
+  } else {
+    gfx->IdentityMatrix();
+    extent = gfx->GetUserFillExtent();
+  }
+
+  mRect = nsSVGUtils::ToBoundingPixelRect(extent);
 
   return NS_OK;
 }
@@ -473,21 +523,18 @@ nsSVGGlyphFrame::GetBBox(nsIDOMSVGRect **_retval)
 
   nsSVGAutoGlyphHelperContext ctx(this, text, getter_Transfers(cp));
 
-  nsresult rv = GetGlobalTransform(ctx);
+  gfxContext *gfx = ctx.GetContext();
+  if (!gfx)
+    return NS_ERROR_OUT_OF_MEMORY;
+
+  nsresult rv = GetGlobalTransform(gfx);
   NS_ENSURE_SUCCESS(rv, rv);
 
-  if (!cp)
-    cairo_move_to(ctx, mX, mY);
+  LoopCharacters(gfx, text, cp, STROKE);
+  gfx->IdentityMatrix();
+  gfxRect rect = gfx->GetUserFillExtent();
 
-  LoopCharacters(ctx, text, cp, cairo_text_path);
-
-  cairo_identity_matrix(ctx);
-
-  double xmin, ymin, xmax, ymax;
-
-  cairo_fill_extents(ctx, &xmin, &ymin, &xmax, &ymax);
-
-  return NS_NewSVGRect(_retval, xmin, ymin, xmax - xmin, ymax - ymin);
+  return NS_NewSVGRect(_retval, rect);
 }
 
 //----------------------------------------------------------------------
@@ -540,11 +587,9 @@ nsSVGGlyphFrame::GetCharacterData(nsAString & aCharacterData)
 
 nsresult
 nsSVGGlyphFrame::GetCharacterPosition(gfxContext *aContext,
-                                      const nsAString &aText,
+                                      const nsString &aText,
                                       nsSVGCharacterPosition **aCharacterPosition)
 {
-  cairo_t *ctx = aContext->GetCairo();
-
   *aCharacterPosition = nsnull;
 
   NS_ASSERTION(!aText.IsEmpty(), "no text");
@@ -565,20 +610,18 @@ nsSVGGlyphFrame::GetCharacterPosition(gfxContext *aContext,
   float length = data->GetLength();
   PRUint32 strLength = aText.Length();
 
+  nsAutoPtr<gfxTextRun> textRun(GetTextRun(aContext, aText));
+  if (!textRun)
+    return NS_ERROR_OUT_OF_MEMORY;
+
   nsSVGCharacterPosition *cp = new nsSVGCharacterPosition[strLength];
 
   for (PRUint32 k = 0; k < strLength; k++)
     cp[k].draw = PR_FALSE;
 
-  float x = mX;
+  float x = mPosition.x;
   for (PRUint32 i = 0; i < strLength; i++) {
-
-    cairo_text_extents_t extent;
-
-    cairo_text_extents(ctx,
-                       NS_ConvertUTF16toUTF8(Substring(aText, i, 1)).get(),
-                       &extent);
-    float halfAdvance = extent.x_advance / 2.0;
+    float halfAdvance = textRun->GetAdvanceWidth(i, 1, nsnull) / 2.0;
 
     /* have we run off the end of the path? */
     if (x + halfAdvance > length)
@@ -591,10 +634,10 @@ nsSVGGlyphFrame::GetCharacterPosition(gfxContext *aContext,
       // add y (normal)
       // add rotation
       // move point back along tangent
-      gfxPoint pt = data->FindPoint(gfxPoint(x + halfAdvance, mY),
+      gfxPoint pt = data->FindPoint(gfxPoint(x + halfAdvance, mPosition.y),
                                     &(cp[i].angle));
-      cp[i].x = pt.x - cos(cp[i].angle) * halfAdvance;
-      cp[i].y = pt.y - sin(cp[i].angle) * halfAdvance;
+      cp[i].pos =
+        pt - gfxPoint(cos(cp[i].angle), sin(cp[i].angle)) * halfAdvance;
     }
     x += 2 * halfAdvance;
   }
@@ -751,8 +794,7 @@ nsSVGGlyphFrame::GetHighlight(PRUint32 *charnum, PRUint32 *nchars,
 NS_IMETHODIMP_(void)
 nsSVGGlyphFrame::SetGlyphPosition(float x, float y)
 {
-  mX = x;
-  mY = y;
+  mPosition.MoveTo(x, y);
   UpdateGeometry(PR_TRUE, PR_FALSE);
 }
 
@@ -768,35 +810,26 @@ nsSVGGlyphFrame::GetStartPositionOfChar(PRUint32 charnum, nsIDOMSVGPoint **_retv
 
   nsSVGAutoGlyphHelperContext ctx(this, text, getter_Transfers(cp));
 
-  float x, y;
+  gfxPoint pt;
 
   if (cp) {
     if (cp[charnum].draw == PR_FALSE) {
       return NS_ERROR_DOM_INDEX_SIZE_ERR;
     }
 
-    x = cp[charnum].x;
-    y = cp[charnum].y;
-
+    pt = cp[charnum].pos;
   } else {
-    x = mX;
-    y = mY;
+    pt = mPosition;
 
     if (charnum > 0) {
-      cairo_text_extents_t extent;
-
-      cairo_text_extents(ctx,
-                         NS_ConvertUTF16toUTF8(Substring(text,
-                                                         0,
-                                                         charnum)).get(),
-                         &extent);
-
-      x += extent.x_advance;
-      y += extent.y_advance;
+      gfxTextRun *textRun = ctx.GetTextRun();
+      if (!textRun)
+        return NS_ERROR_OUT_OF_MEMORY;
+      pt.x += textRun->GetAdvanceWidth(0, charnum, nsnull);
     }
   }
 
-  return NS_NewSVGPoint(_retval, x, y);
+  return NS_NewSVGPoint(_retval, pt.x, pt.y);
 }
 
 NS_IMETHODIMP
@@ -810,31 +843,27 @@ nsSVGGlyphFrame::GetEndPositionOfChar(PRUint32 charnum, nsIDOMSVGPoint **_retval
   nsAutoArrayPtr<nsSVGCharacterPosition> cp;
 
   nsSVGAutoGlyphHelperContext ctx(this, text, getter_Transfers(cp));
-
-  cairo_text_extents_t extent;
+  gfxTextRun *textRun = ctx.GetTextRun();
+  if (!textRun)
+    return NS_ERROR_OUT_OF_MEMORY;
 
   if (cp) {
     if (cp[charnum].draw == PR_FALSE) {
       return NS_ERROR_DOM_INDEX_SIZE_ERR;
     }
 
-    cairo_text_extents(ctx, 
-                       NS_ConvertUTF16toUTF8(Substring(text, charnum, 1)).get(),
-                       &extent);
-
-    float s = sin(cp[charnum].angle);
-    float c = cos(cp[charnum].angle);
+    float advance = textRun->GetAdvanceWidth(charnum, 1, nsnull);
 
     return NS_NewSVGPoint(_retval,
-             cp[charnum].x + extent.x_advance * c - extent.y_advance * s,
-             cp[charnum].y + extent.y_advance * c + extent.x_advance * s);
+                          cp[charnum].pos.x + advance * cos(cp[charnum].angle),
+                          cp[charnum].pos.y + advance * sin(cp[charnum].angle));
   }
 
-  cairo_text_extents(ctx, 
-                     NS_ConvertUTF16toUTF8(Substring(text, 0, charnum + 1)).get(),
-                     &extent);
-
-  return NS_NewSVGPoint(_retval, mX + extent.x_advance, mY + extent.y_advance);
+  return NS_NewSVGPoint(_retval,
+                        mPosition.x + textRun->GetAdvanceWidth(0,
+                                                               charnum + 1,
+                                                               nsnull),
+                        mPosition.y);
 }
 
 NS_IMETHODIMP
@@ -848,60 +877,47 @@ nsSVGGlyphFrame::GetExtentOfChar(PRUint32 charnum, nsIDOMSVGRect **_retval)
   nsAutoArrayPtr<nsSVGCharacterPosition> cp;
 
   nsSVGAutoGlyphHelperContext ctx(this, text, getter_Transfers(cp));
+  gfxTextRun *textRun = ctx.GetTextRun();
+  if (!textRun)
+    return NS_ERROR_OUT_OF_MEMORY;
 
-  cairo_text_extents_t extent;
-  cairo_text_extents(ctx,
-                     NS_ConvertUTF16toUTF8(Substring(text, charnum, 1)).get(),
-                     &extent);
+  gfxTextRun::Metrics metrics =
+    textRun->MeasureText(charnum, 1, PR_FALSE, nsnull);
 
   if (cp) {
     if (cp[charnum].draw == PR_FALSE) {
       return NS_ERROR_DOM_INDEX_SIZE_ERR;
     }
 
-    cairo_matrix_t matrix;
-    cairo_get_matrix(ctx, &matrix);
-    cairo_move_to(ctx, cp[charnum].x, cp[charnum].y);
-    cairo_rotate(ctx, cp[charnum].angle);
+    gfxContext *gfx = ctx.GetContext();
+    if (!gfx)
+      return NS_ERROR_OUT_OF_MEMORY;
 
-    cairo_rel_move_to(ctx, extent.x_bearing, extent.y_bearing);
-    cairo_rel_line_to(ctx, extent.width, 0);
-    cairo_rel_line_to(ctx, 0, extent.height);
-    cairo_rel_line_to(ctx, -extent.width, 0);
-    cairo_close_path(ctx);
-    cairo_identity_matrix(ctx);
+    gfxMatrix matrix = gfx->CurrentMatrix();
 
-    double xmin, ymin, xmax, ymax;
+    gfx->MoveTo(cp[charnum].pos);
+    gfx->Rotate(cp[charnum].angle);
 
-    cairo_fill_extents(ctx, &xmin, &ymin, &xmax, &ymax);
+    gfx->Rectangle(metrics.mBoundingBox + gfx->CurrentPoint());
 
-    cairo_set_matrix(ctx, &matrix);
+    gfx->IdentityMatrix();
 
-    return NS_NewSVGRect(_retval, xmin, ymin, xmax - xmin, ymax - ymin);
+    gfxRect rect = gfx->GetUserFillExtent();
+
+    gfx->SetMatrix(matrix);
+
+    return NS_NewSVGRect(_retval, rect);
   }
 
-  float x = mX;
-  float y = mY;
-
-  x += extent.x_bearing;
-  y += extent.y_bearing;
-
-  cairo_text_extents_t precedingExtent;
+  gfxPoint pt = mPosition;
 
   if (charnum > 0) {
     // add the space taken up by the text which comes before charnum
     // to the position of the charnum character
-    cairo_text_extents(ctx,
-                       NS_ConvertUTF16toUTF8(Substring(text,
-                                                       0,
-                                                       charnum)).get(),
-                       &precedingExtent);
-
-    x += precedingExtent.x_advance;
-    y += precedingExtent.y_advance;
+    pt.x += textRun->GetAdvanceWidth(0, charnum, nsnull);
   }
 
-  return NS_NewSVGRect(_retval, x, y, extent.width, extent.height);
+  return NS_NewSVGRect(_retval, metrics.mBoundingBox + pt);
 }
 
 NS_IMETHODIMP
@@ -932,25 +948,31 @@ NS_IMETHODIMP_(float)
 nsSVGGlyphFrame::GetBaselineOffset(PRUint16 baselineIdentifier)
 {
   float _retval;
-  cairo_font_extents_t extents;
 
-  nsSVGAutoGlyphHelperContext ctx(this);
+  nsAutoString text;
+  GetCharacterData(text);
 
-  cairo_font_extents(ctx, &extents);
+  nsSVGAutoGlyphHelperContext ctx(this, text);
+  gfxTextRun *textRun = ctx.GetTextRun();
+  if (!textRun)
+    return 0.0f;
+
+  gfxTextRun::Metrics metrics =
+    textRun->MeasureText(0, text.Length(), PR_FALSE, nsnull);
 
   switch (baselineIdentifier) {
   case BASELINE_HANGING:
     // not really right, but the best we can do with the information provided
     // FALLTHROUGH
   case BASELINE_TEXT_BEFORE_EDGE:
-    _retval = -extents.ascent;
+    _retval = -metrics.mAscent;
     break;
   case BASELINE_TEXT_AFTER_EDGE:
-    _retval = extents.descent;
+    _retval = metrics.mDescent;
     break;
   case BASELINE_CENTRAL:
   case BASELINE_MIDDLE:
-    _retval = - (extents.ascent - extents.descent) / 2.0;
+    _retval = - (metrics.mAscent - metrics.mDescent) / 2.0;
     break;
   case BASELINE_ALPHABETIC:
   default:
@@ -969,14 +991,12 @@ nsSVGGlyphFrame::GetAdvance()
     return 0.0f;
   }
 
-  nsSVGAutoGlyphHelperContext ctx(this);
+  nsSVGAutoGlyphHelperContext ctx(this, text);
+  gfxTextRun *textRun = ctx.GetTextRun();
+  if (!textRun)
+    return 0.0f;
 
-  cairo_text_extents_t extents;
-  cairo_text_extents(ctx, 
-                     NS_ConvertUTF16toUTF8(text).get(),
-                     &extents);
-  
-  return extents.x_advance;
+  return textRun->GetAdvanceWidth(0, text.Length(), nsnull);
 }
 
 NS_IMETHODIMP_(nsSVGTextPathFrame*) 
@@ -1104,19 +1124,7 @@ nsSVGGlyphFrame::GetNumberOfChars()
 NS_IMETHODIMP_(float)
 nsSVGGlyphFrame::GetComputedTextLength()
 {
-  nsAutoString text;
-  if (!GetCharacterData(text)) {
-    return 0.0f;
-  }
-
-  nsSVGAutoGlyphHelperContext ctx(this);
-
-  cairo_text_extents_t extent;
-  cairo_text_extents(ctx,
-                     NS_ConvertUTF16toUTF8(text).get(),
-                     &extent);
-
-  return fabs(extent.x_advance) + fabs(extent.y_advance);
+  return GetAdvance();
 }
 
 NS_IMETHODIMP_(float)
@@ -1125,14 +1133,12 @@ nsSVGGlyphFrame::GetSubStringLength(PRUint32 charnum, PRUint32 fragmentChars)
   nsAutoString text;
   GetCharacterData(text);
 
-  nsSVGAutoGlyphHelperContext ctx(this);
+  nsSVGAutoGlyphHelperContext ctx(this, text);
+  gfxTextRun *textRun = ctx.GetTextRun();
+  if (!textRun)
+    return 0.0f;
 
-  cairo_text_extents_t extent;
-  cairo_text_extents(ctx,
-                     NS_ConvertUTF16toUTF8(Substring(text, charnum, fragmentChars)).get(),
-                     &extent);
-
-  return fabs(extent.x_advance) + fabs(extent.y_advance);
+  return textRun->GetAdvanceWidth(charnum, fragmentChars, nsnull);
 }
 
 NS_IMETHODIMP_(PRInt32)
@@ -1149,55 +1155,48 @@ nsSVGGlyphFrame::GetCharNumAtPosition(nsIDOMSVGPoint *point)
 
   nsSVGAutoGlyphHelperContext ctx(this, text, getter_Transfers(cp));
 
-  float x, y;
+  gfxPoint pt;
   if (!cp) {
-    x = mX;
-    y = mY;
+    pt = mPosition;
   }
 
+  gfxContext *gfx = ctx.GetContext();
+  gfxTextRun *textRun = ctx.GetTextRun();
+  if (!gfx || !textRun)
+    return NS_ERROR_OUT_OF_MEMORY;
+
   for (PRUint32 charnum = 0; charnum < text.Length(); charnum++) {
     /* character actually on the path? */
     if (cp && cp[charnum].draw == PR_FALSE)
       continue;
 
-    cairo_matrix_t matrix;
-    cairo_get_matrix(ctx, &matrix);
-    cairo_new_path(ctx);
+    gfxMatrix matrix = gfx->CurrentMatrix();
+    gfx->NewPath();
 
     if (cp) {
-      cairo_move_to(ctx, cp[charnum].x, cp[charnum].y);
-      cairo_rotate(ctx, cp[charnum].angle);
+      gfx->MoveTo(cp[charnum].pos);
+      gfx->Rotate(cp[charnum].angle);
     } else {
       if (charnum > 0) {
-        cairo_text_extents_t extent;
-
-        cairo_text_extents(ctx,
-                           NS_ConvertUTF16toUTF8(Substring(text,
-                                                           0,
-                                                           charnum)).get(),
-                           &extent);
-        cairo_move_to(ctx, x + extent.x_advance, y + extent.y_advance);
+        gfx->MoveTo(pt + gfxPoint(textRun->GetAdvanceWidth(0, charnum, nsnull),
+                                  0));
       } else {
-        cairo_move_to(ctx, x, y);
+        gfx->MoveTo(pt);
       }
     }
-    cairo_text_extents_t extent;
-    cairo_text_extents(ctx,
-                       NS_ConvertUTF16toUTF8(Substring(text, charnum, 1)).get(),
-                       &extent);
 
-    cairo_rel_move_to(ctx, extent.x_bearing, extent.y_bearing);
-    cairo_rel_line_to(ctx, extent.width, 0);
-    cairo_rel_line_to(ctx, 0, extent.height);
-    cairo_rel_line_to(ctx, -extent.width, 0);
-    cairo_close_path(ctx);
+    gfxTextRun::Metrics metrics =
+      textRun->MeasureText(charnum, 1, PR_FALSE, nsnull);
 
-    cairo_identity_matrix(ctx);
-    if (cairo_in_fill(ctx, xPos, yPos)) {
+    gfx->Rectangle(metrics.mBoundingBox + gfx->CurrentPoint());
+
+    gfx->IdentityMatrix();
+    if (gfx->PointInFill(gfxPoint(xPos, yPos))) {
+      gfx->SetMatrix(matrix);
       return charnum;
     }
 
-    cairo_set_matrix(ctx, &matrix);
+    gfx->SetMatrix(matrix);
   }
   return -1;
 }
@@ -1237,68 +1236,6 @@ nsSVGGlyphFrame::SetWhitespaceHandling(PRUint8 aWhitespaceHandling)
 //----------------------------------------------------------------------
 //
 
-void nsSVGGlyphFrame::SelectFont(gfxContext *aContext)
-{
-  cairo_t *ctx = aContext->GetCairo();
-
-  const nsStyleFont* fontData = GetStyleFont();
-  nsFont font = fontData->mFont;
-
-  // XXX eventually we will have to treat decorations separately from
-  // fonts, because they can have a different color than the current
-  // glyph.
-  
-  NS_ASSERTION(mParent, "no parent");
-  nsStyleContext *parentContext = mParent->GetStyleContext();
-  NS_ASSERTION(parentContext, "no style context on parent");
-  
-  PRUint8 styleDecorations =
-    parentContext->GetStyleTextReset()->mTextDecoration;
-  if (styleDecorations & NS_STYLE_TEXT_DECORATION_UNDERLINE)
-    font.decorations |= NS_FONT_DECORATION_UNDERLINE;
-  if (styleDecorations & NS_STYLE_TEXT_DECORATION_OVERLINE)
-    font.decorations |= NS_FONT_DECORATION_OVERLINE;
-  if (styleDecorations & NS_STYLE_TEXT_DECORATION_LINE_THROUGH)
-    font.decorations |= NS_FONT_DECORATION_LINE_THROUGH;    
-  
-  cairo_font_slant_t slant;
-  cairo_font_weight_t weight = CAIRO_FONT_WEIGHT_NORMAL;
-
-  switch (font.style) {
-  case NS_FONT_STYLE_NORMAL:
-    slant = CAIRO_FONT_SLANT_NORMAL;
-    break;
-  case NS_FONT_STYLE_ITALIC:
-    slant = CAIRO_FONT_SLANT_ITALIC;
-    break;
-  case NS_FONT_STYLE_OBLIQUE:
-    slant = CAIRO_FONT_SLANT_OBLIQUE;
-    break;
-  }
-
-  if (font.weight % 100 == 0) {
-    if (font.weight >= 600)
-      weight = CAIRO_FONT_WEIGHT_BOLD;
-  } else if (font.weight % 100 < 50) {
-    weight = CAIRO_FONT_WEIGHT_BOLD;
-  }
-
-  nsAutoString family;
-  font.GetFirstFamily(family);
-  cairo_select_font_face(ctx,
-                         NS_ConvertUTF16toUTF8(family).get(),
-                         slant,
-                         weight);
-
-  // Since SVG has its own scaling, we really don't want
-  // fonts in SVG to respond to the browser's "TextZoom"
-  // (Ctrl++,Ctrl+-)
-  nsPresContext *presContext = PresContext();
-  float textZoom = presContext->TextZoom();
-
-  cairo_set_font_size(ctx, presContext->AppUnitsToDevPixels(fontData->mSize) / textZoom);
-}
-
 void nsSVGGlyphFrame::UpdateGeometry(PRBool bRedraw,
                                      PRBool suppressInvalidation)
 {
@@ -1343,52 +1280,47 @@ nsSVGGlyphFrame::ContainsPoint(float x, float y)
   nsAutoArrayPtr<nsSVGCharacterPosition> cp;
 
   nsSVGAutoGlyphHelperContext ctx(this, text, getter_Transfers(cp));
+  gfxContext *gfx = ctx.GetContext();
+  gfxTextRun *textRun = ctx.GetTextRun();
+  if (!gfx || !textRun)
+    return NS_ERROR_OUT_OF_MEMORY;
 
-  nsresult rv = GetGlobalTransform(ctx);
+  nsresult rv = GetGlobalTransform(gfx);
   NS_ENSURE_SUCCESS(rv, PR_FALSE);
 
-  float xx = 0, yy = 0;
+  gfxPoint pt;
   if (!cp) {
-    xx = mX;
-    yy = mY;
+    pt = mPosition;
   }
 
-  cairo_matrix_t matrix;
-
   for (PRUint32 i = 0; i < text.Length(); i++) {
     /* character actually on the path? */
     if (cp && cp[i].draw == PR_FALSE)
       continue;
 
-    cairo_get_matrix(ctx, &matrix);
+    gfxMatrix matrix = gfx->CurrentMatrix();
 
     if (cp) {
-      cairo_move_to(ctx, cp[i].x, cp[i].y);
-      cairo_rotate(ctx, cp[i].angle);
+      gfx->MoveTo(cp[i].pos);
+      gfx->Rotate(cp[i].angle);
     } else {
-      cairo_move_to(ctx, xx, yy);
+      gfx->MoveTo(pt);
     }
 
-    cairo_text_extents_t extent;
-    cairo_text_extents(ctx,
-                       NS_ConvertUTF16toUTF8(Substring(text, i, 1)).get(),
-                       &extent);
-    cairo_rel_move_to(ctx, extent.x_bearing, extent.y_bearing);
-    cairo_rel_line_to(ctx, extent.width, 0);
-    cairo_rel_line_to(ctx, 0, extent.height);
-    cairo_rel_line_to(ctx, -extent.width, 0);
-    cairo_close_path(ctx);
+    gfxTextRun::Metrics metrics =
+      textRun->MeasureText(i, 1, PR_FALSE, nsnull);
 
-    cairo_set_matrix(ctx, &matrix);
+    gfx->Rectangle(metrics.mBoundingBox + gfx->CurrentPoint());
+
+    gfx->SetMatrix(matrix);
 
     if (!cp) {
-      xx += extent.x_advance;
-      yy += extent.y_advance;
+      pt.x += metrics.mAdvanceWidth;
     }
   }
 
-  cairo_identity_matrix(ctx);
-  return cairo_in_fill(ctx, x, y);
+  gfx->IdentityMatrix();
+  return gfx->PointInFill(gfxPoint(x, y));
 }
 
 nsresult
@@ -1410,15 +1342,38 @@ nsSVGGlyphFrame::GetGlobalTransform(gfxContext *aContext)
   return NS_OK;
 }
 
+gfxTextRun *
+nsSVGGlyphFrame::GetTextRun(gfxContext *aCtx, const nsString &aText)
+{
+  // XXX: should really pass in GetPresContext()->AppUnitsPerDevPixel()
+  // instead of "1" and do the appropriate unit conversions when sending
+  // coordinates into thebes and pulling metrics out.
+  //
+  // References:
+  //   https://bugzilla.mozilla.org/show_bug.cgi?id=375141
+  //   http://weblogs.mozillazine.org/roc/archives/2007/03/text_text_text.html
+
+  gfxTextRunFactory::Parameters params =
+    { aCtx, nsnull, nsnull,
+      nsnull, nsnull, nsnull,
+      1, // see note above
+      0 };
+
+  if (!mFontGroup)
+    return nsnull;
+
+  return mFontGroup->MakeTextRun(aText.get(), aText.Length(), &params);
+}
+
 //----------------------------------------------------------------------
 // helper class
 
 nsSVGGlyphFrame::nsSVGAutoGlyphHelperContext::nsSVGAutoGlyphHelperContext(
     nsSVGGlyphFrame *aSource,
-    const nsAString &aText,
+    const nsString &aText,
     nsSVGCharacterPosition **cp)
 {
-  Init(aSource);
+  Init(aSource, aText);
 
   nsresult rv = aSource->GetCharacterPosition(mCT, aText, cp);
   if NS_FAILED(rv) {
@@ -1426,8 +1381,10 @@ nsSVGGlyphFrame::nsSVGAutoGlyphHelperContext::nsSVGAutoGlyphHelperContext(
   }
 }
 
-void nsSVGGlyphFrame::nsSVGAutoGlyphHelperContext::Init(nsSVGGlyphFrame *aSource)
+void
+nsSVGGlyphFrame::nsSVGAutoGlyphHelperContext::Init(nsSVGGlyphFrame *aSource,
+                                                   const nsString &aText)
 {
   mCT = new gfxContext(nsSVGUtils::GetThebesComputationalSurface());
-  aSource->SelectFont(mCT);
+  mTextRun = aSource->GetTextRun(mCT, aText);
 }

layout/svg/base/src/nsSVGGlyphFrame.h

@@ -43,7 +43,9 @@
 #include "nsISVGGlyphFragmentLeaf.h"
 #include "nsISVGChildFrame.h"
 #include "gfxContext.h"
+#include "gfxFont.h"
 
+struct nsSVGCharacterPosition;
 class nsSVGTextFrame;
 class nsSVGGlyphFrame;
 
@@ -151,8 +153,8 @@ public:
 
 protected:
   struct nsSVGCharacterPosition {
+    gfxPoint pos;
     gfxFloat angle;
-    float x, y;
     PRBool draw;
   };
 
@@ -161,45 +163,44 @@ protected:
   class nsSVGAutoGlyphHelperContext;
   friend class nsSVGAutoGlyphHelperContext;
 
-  // A helper class to deal with temporary cairo contexts.
-  // It destroys the context when it goes out of scope.
+  // A helper class to deal with gfxTextRuns and temporary thebes
+  // contexts.  It destroys them when it goes out of scope.
   class nsSVGAutoGlyphHelperContext
   {
   public:
-    nsSVGAutoGlyphHelperContext(nsSVGGlyphFrame *aSource)
+    nsSVGAutoGlyphHelperContext(nsSVGGlyphFrame *aSource,
+                                const nsString &aText)
     {
-       Init(aSource);
+      Init(aSource, aText);
     }
 
     nsSVGAutoGlyphHelperContext(nsSVGGlyphFrame *aSource,
-                                const nsAString &aText,
+                                const nsString &aText,
                                 nsSVGCharacterPosition **cp);
 
-    operator gfxContext * ()
-    {
-      return mCT;
-    }
-
-    operator cairo_t * ()
-    {
-      return mCT->GetCairo();
-    }
+    gfxContext *GetContext() { return mCT; }
+    gfxTextRun *GetTextRun() { return mTextRun; }
 
   private:
-    void Init (nsSVGGlyphFrame *aSource);
+    void Init(nsSVGGlyphFrame *aSource, const nsString &aText);
 
     nsRefPtr<gfxContext> mCT;
+    nsAutoPtr<gfxTextRun> mTextRun;
   };
 
-  void SelectFont(gfxContext *aContext);
+  gfxTextRun *GetTextRun(gfxContext *aCtx,
+                         const nsString &aText);
+
   PRBool GetCharacterData(nsAString & aCharacterData);
   nsresult GetCharacterPosition(gfxContext *aContext,
-                                const nsAString &aText,
+                                const nsString &aText,
                                 nsSVGCharacterPosition **aCharacterPosition);
-  static void LoopCharacters(cairo_t *aCtx,
-                             const nsAString &aText,
+
+  enum FillOrStroke { FILL, STROKE};
+
+  void LoopCharacters(gfxContext *aCtx, const nsString &aText,
                       const nsSVGCharacterPosition *aCP,
-                             void (*aFunc)(cairo_t *cr, const char *utf8));
+                      FillOrStroke aFillOrStroke);
 
   void UpdateGeometry(PRBool bRedraw, PRBool suppressInvalidation);
   void UpdateMetrics();
@@ -208,7 +209,9 @@ protected:
   nsresult GetHighlight(PRUint32 *charnum, PRUint32 *nchars,
                         nscolor *foreground, nscolor *background);
 
-  float mX, mY;
+  nsRefPtr<gfxFontGroup> mFontGroup;
+  nsAutoPtr<gfxFontStyle> mFontStyle;
+  gfxPoint mPosition;
   PRUint8 mWhitespaceHandling;
 };