144665 - common printing interface for Postscript and TrueType fonts

Status: VERIFIED FIXED

(Core :: Internationalization, enhancement)

Description

[kill this account]

to facilitate printing using both Postscript fonts and TrueType fonts we need a 
common (virtual) class interface so the font details are hidden from the 
printing code.

Comment 1

[Pete Zha]

taking

Comment 2

[Pete Zha]

per discuss with Brain:
This virtual class need following functions and data(Just for example)
 inline int SupportsChar(PRUnichar aChar) { return mCCMap &&
CCMAP_HAS_CHAR(mCCMap, aChar); };
 virtual gint GetWidth(const PRUnichar* aString, PRUint32 aLength) = 0;
 virtual gint DrawString(context, nscoord aX, nscoord aY, const PRUnichar*
aString, PRUint32 aLength) = 0;
#ifdef MOZ_MATHML
 virtual nsresult
 GetBoundingMetrics(const PRUnichar*   aString,
                    PRUint32           aLength,
                    nsBoundingMetrics& aBoundingMetrics) = 0;
#endif
data:
PRUint16*              mCCMap;

And the name of this class should be nsFontPS

Comment 3

[Pete Zha]

Attachment: Patch(only add new classes and functions)

This patch only add new class definition and implementation into
nsFontMetricsPS.cpp. It includes following change:
1) Add class nsFontPS which is the base class for this font interface.
2) Add class nsFontPSAFM which inherit from nsFontPS and implement some virtual
functions for nsFontPS
3) Add several inline setter function into nsFontMetricsPS class. This way, the
font interface class, like nsFontPSAFM can set data of nsFontMetricsPS when
realize font.
4) Add a simple inline getter in nsDeviceContextPS to get the mPSObj from it to
implement drawString font interface.
This patch does not change any logic of current code.

Comment 4

[Pete Zha]

Attachment: Patch(only add new classes and functions)

This patch only add new class definition and implementation into
nsFontMetricsPS.cpp. It includes following change:
1) Add class nsFontPS which is the base class for this font interface.
2) Add class nsFontPSAFM which inherit from nsFontPS and implement some virtual
functions for nsFontPS
3) Add several inline setter function into nsFontMetricsPS class. This way, the
font interface class, like nsFontPSAFM can set data of nsFontMetricsPS when
realize font.
4) Add a simple inline getter in nsDeviceContextPS to get the mPSObj from it to
implement drawString font interface.
This patch does not change any logic of current code.

Comment 5

[Pete Zha]

Comment on attachment 100220 [details] [diff] [review]
Patch(only add new classes and functions)

oops, sorry for adding this patch twice because of a network problem.

Comment 6

[Pete Zha]

Comment on attachment 100221 [details] [diff] [review]
Patch(only add new classes and functions)

Needs work to modify code in ps module to use font interface.

Comment 7

[Pete Zha]

Attachment: Patch v1

First working patch. Ready for r=/sr=...
Issues:
1) I'm not sure how to implement GetBoundingMetrics. Maybe do it later.
2) Need more testing I think.

Comment 8

[Pete Zha]

Attachment: Patch v2

This patch fix some problem per Brian's comments from email:
>1) When I printout the www.mozilla.org page with the patch I see overlapping
>text. I do not see any overlap without the patch.
It's caused by a typo in nsFontMetricsPS.h. I have fixed it in this patch
inline void SetSpaceWidth(nscoord aSpaceWidth) { mSpaceWidth = aSpaceWidth; };
vs
inline void SetSpaceWidth(nscoord aAveCharWidth) { mAveCharWidth =
aAveCharWidth; };

>2) Can we add a comment here saying "more font types to come..." or something
>like that?
>+nsFontPS::FindFont(const nsFont& aFont, nsIFontMetrics* aFontMetrics)
done

>3) Nit: I note that the order of the 2 nsRenderingContextPS::DrawString()
>routines was changed. I'm curious if there was some reason for this as the
diff >would be smaller if the functions were not reordered.
I have changed back to orignial order for these two function

Comment 9

[Pete Zha]

Comment on attachment 100527 [details] [diff] [review]
Patch v2

>+   * In the furture, this function is responsible for font selection
Oops, here is a typeo again. "furture" should be "future" :-P

Comment 10

[kill this account]

1) nit: can we change "height" to "size"?

+  nscoord height = NSToCoordRound(fontSize * dev2app);
+  aFontMetrics->SetHeight(height);
+  aFontMetrics->SetEmHeight(height);
+  aFontMetrics->SetMaxAdvance(height);
+  aFontMetrics->SetMaxHeight(height);

2) is this the points to twips constant

+  mAFMInfo->Init(mFont->size / 20);

3) how does the memory work here (where does the copy happen):

  mFamilyName = (char*)mAFMInfo->mPSFontInfo->mFamilyName;

...

  if (mFamilyName) {
    delete mFamilyName;

Comment 11

[Pete Zha]

Attachment: Patch v3

>1) nit: can we change "height" to "size"?
done

>2) is this the points to twips constant
>+  mAFMInfo->Init(mFont->size / 20);
I think so.

>3) how does the memory work here (where does the copy happen):
>  mFamilyName = (char*)mAFMInfo->mPSFontInfo->mFamilyName;
I'm now using nsAutoString for mFamilyName.

Comment 12

[kill this account]

Comment on attachment 100678 [details] [diff] [review]
Patch v3

r=[e-mail]

Comment 13

[jag (Peter Annema)]

Comment on attachment 100678 [details] [diff] [review]
Patch v3

>+  inline nsAutoString GetFamilyName() { return mFamilyName; };

You shouldn't return this by value. It's a string class that embeds a 128 byte
buffer. If you know that your nsFontPS object lives longer than the code that
uses the result of |GetFamilyName()| you can return a |const nsString&| to it.

>+  nsAutoString             mFamilyName;

Also don't store it as a nsAutoString. For member values it's typically better
to use a nsString, which doesn't take up as much space.

With that fixed, sr=jag

Comment 14

[Pete Zha]

Attachment: Patch v4 with jag's comments

Using nsString instead of nsAutoString and return nsString& instead of
nsAutoString

Comment 15

[Pete Zha]

Comment on attachment 100844 [details] [diff] [review]
Patch v4 with jag's comments

carry r=/sr=

Comment 16

[Pete Zha]

checked in trunk

Comment 17

[Pete Zha]

Attachment: Arrange code

Move SetupFontAndColor from nsRenderContextPS into nsFontPS interface.
Move mFontIndex and mFamilyName from nsFontPS into nsFontPSAFM.

Comment 18

[Yuying Long]

True type printing is working on 01-21 trunk build / Linux RH7.2, mark this as
verified.