Update the SkDocument interface to allow for 1) abort won't emit pdf, 2) close can report success/f…

src/pdf/SkPDFDeviceFlattener.cpp

Index: src/pdf/SkPDFDeviceFlattener.cpp
diff --git a/src/pdf/SkPDFDeviceFlattener.cpp b/src/pdf/SkPDFDeviceFlattener.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..85c93a1893f5bdeebc66546c6f3673dfbea4ea45
--- /dev/null
+++ b/src/pdf/SkPDFDeviceFlattener.cpp
@@ -0,0 +1,134 @@
+/*
+ * Copyright 2013 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "SkPDFDeviceFlattener.h"
+
+#include "SkDraw.h"
+
+static SkISize SkSizeToISize(const SkSize& size) {
+    return SkISize::Make(SkScalarRoundToInt(size.width()), SkScalarRoundToInt(size.height()));
+}
+
+SkPDFDeviceFlattener::SkPDFDeviceFlattener(const SkSize& pageSize, const SkRect* trimBox)
+            : SkPDFDevice(SkSizeToISize(pageSize),
+                          SkSizeToISize(pageSize),
+                          SkMatrix::I()) {
+    // TODO(edisonn): store the trimbox on emit.
+}
+
+SkPDFDeviceFlattener::~SkPDFDeviceFlattener() {
+}
+
+void SkPDFDeviceFlattener::drawPoints(const SkDraw& d, SkCanvas::PointMode mode,
+                                      size_t count, const SkPoint points[],
+                                      const SkPaint& paint) {
+    if (!mustFlatten(d)) {
+        INHERITED::drawPoints(d, mode, count, points, paint);
+        return;
+    }
+

[vandebo (ex-Chrome), 2013/10/09 16:52:32]

I think shaders can affect drawPoints too... lines, polygons...

[edisonn, 2013/10/10 18:35:15]

Done.

+    SkPoint* flattenedPoints = SkNEW_ARRAY(SkPoint, count);
+    d.fMatrix->mapPoints(flattenedPoints, points, count);
+    SkDraw draw(d);
+    SkMatrix identity = SkMatrix::I();
+    draw.fMatrix = &identity;
+    INHERITED::drawPoints(draw, mode, count, flattenedPoints, paint);
+    SkDELETE_ARRAY(flattenedPoints);
+}
+
+void SkPDFDeviceFlattener::drawRect(const SkDraw& d, const SkRect& r, const SkPaint& paint) {
+    if (!mustFlatten(d)) {
+        INHERITED::drawRect(d, r, paint);
+        return;
+    }
+
+    SkPath path;
+    path.addRect(r);
+    path.transform(*d.fMatrix);
+    SkDraw draw(d);
+    SkMatrix matrix = SkMatrix::I();
+    draw.fMatrix = &matrix;
+
+    SkPaint paintFlatten = paint;
+    if (paintFlatten.getShader()) {

[vandebo (ex-Chrome), 2013/10/09 16:52:32]

Consider pulling this block of code into a function, it's used twice and may be
used more in the future.

[edisonn, 2013/10/10 18:35:15]

Done.

+        SkMatrix local = paintFlatten.getShader()->getLocalMatrix();
+        local.preConcat(*d.fMatrix);
+        paintFlatten.getShader()->setLocalMatrix(local);
+    }
+
+    INHERITED::drawPath(draw, path, paintFlatten, NULL, true);
+}
+
+void SkPDFDeviceFlattener::drawPath(const SkDraw& d, const SkPath& origpath,
+                                    const SkPaint& paint, const SkMatrix* prePathMatrix,
+                                    bool pathIsMutable) {
+    if (!mustFlatten(d) && !(prePathMatrix && prePathMatrix->hasPerspective())) {
+        INHERITED::drawPath(d, origpath, paint, prePathMatrix, pathIsMutable);
+        return;
+    }
+
+    SkPath path;
+    path.addPath(origpath);

[reed1, 2013/10/09 17:03:54]

if your intention is to always make a copy of the path, just calling the
copy-constructor is probably clearer/slightly-faster.

SkPath path(origpath);

[edisonn, 2013/10/10 18:35:15]

Done - using pathIsMutable

+    if (prePathMatrix) {
+        path.transform(*prePathMatrix);

[vandebo (ex-Chrome), 2013/10/09 16:52:32]

The comment in SkDevice.h above drawPath implies that something more may need to
be done here if paint has geometry effects, but I don't understand it.

Mike?

[reed1, 2013/10/09 17:03:54]

Before you can call transform (on line 79) you have to have applied any
stroking, etc. This can easily be done by just calling paint.getFillPath(). The
returned path will have all geometric effects applied, and can be now be
transformed by the CTM.

If that is done (calling getFillPath), then the paint needs to have those
effects removed before calling back into the INHERITED::drawPath (so they don't
get applied twice).

[edisonn, 2013/10/10 18:35:15]

Done.

+    }
+    path.transform(*d.fMatrix);
+    SkDraw draw(d);
+    SkMatrix matrix = SkMatrix::I();
+    draw.fMatrix = &matrix;
+
+    SkPaint paintFlatten = paint;
+    if (paintFlatten.getShader()) {
+        SkMatrix local = *d.fMatrix;
+        local.preConcat(paintFlatten.getShader()->getLocalMatrix());
+
+        paintFlatten.getShader()->setLocalMatrix(local);
+    }
+
+    INHERITED::drawPath(draw, path, paintFlatten, NULL, true);
+}
+
+void SkPDFDeviceFlattener::drawText(const SkDraw& d, const void* text, size_t len,
+                                    SkScalar x, SkScalar y, const SkPaint& paint) {
+    if (mustPathText(d, paint)) {
+        d.drawText_asPaths((const char*)text, len, x, y, paint);
+        return;
+    }
+
+    INHERITED::drawText(d, text, len, x, y, paint);
+}
+
+void SkPDFDeviceFlattener::drawPosText(const SkDraw& d, const void* text, size_t len,
+                                       const SkScalar pos[], SkScalar constY,
+                                       int scalarsPerPos, const SkPaint& paint) {
+    if (mustPathText(d, paint)) {
+        d.drawPosText_asPaths((const char*)text, len, pos, constY, scalarsPerPos, paint);
+        return;
+    }
+    INHERITED::drawPosText(d, text, len,pos, constY,scalarsPerPos, paint);
+}
+
+void SkPDFDeviceFlattener::drawTextOnPath(const SkDraw& d, const void* text, size_t len,
+                                          const SkPath& path, const SkMatrix* matrix,
+                                          const SkPaint& paint) {
+    if (mustPathText(d, paint) || (matrix && matrix->hasPerspective())) {
+        d.drawTextOnPath((const char*)text, len, path, matrix, paint);
+        return;
+    }
+    INHERITED::drawTextOnPath(d, text, len, path, matrix, paint);
+}
+
+bool SkPDFDeviceFlattener::mustFlatten(const SkDraw& d) const {
+    // TODO(edisonn): testability, add flag to force return true.
+    return d.fMatrix->hasPerspective();
+}
+
+bool SkPDFDeviceFlattener::mustPathText(const SkDraw& d, const SkPaint&) {
+    // TODO(edisonn): testability, add flag to force return true.
+    // TODO(edisonn): TBD: How to flatten MaskFilter.
+    return d.fMatrix->hasPerspective();
+}