gecko-dev/gfx/src/nsDeviceContext.cpp

610 lines
17 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
*
* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is mozilla.org code.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1998
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Roland Mainz <Roland.Mainz@informatik.med.uni-giessen.de>
* IBM Corp.
*
* Alternatively, the contents of this file may be used under the terms of
* either of the GNU General Public License Version 2 or later (the "GPL"),
* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#include "nsDeviceContext.h"
#include "nsFont.h"
#include "nsIView.h"
#include "nsGfxCIID.h"
#include "nsVoidArray.h"
#include "nsIFontMetrics.h"
#include "nsHashtable.h"
#include "nsILanguageAtomService.h"
#include "nsIServiceManager.h"
#include "nsUnicharUtils.h"
#include "nsCRT.h"
#include "nsIRenderingContext.h"
#include "gfxUserFontSet.h"
#include "nsIThebesFontMetrics.h"
NS_IMPL_ISUPPORTS3(DeviceContextImpl, nsIDeviceContext, nsIObserver, nsISupportsWeakReference)
DeviceContextImpl::DeviceContextImpl()
{
mAppUnitsPerDevPixel = -1;
mAppUnitsPerInch = -1;
mAppUnitsPerDevNotScaledPixel = -1;
mPixelScale = 1.0f;
mFontCache = nsnull;
mWidget = nsnull;
mFontAliasTable = nsnull;
#ifdef NS_DEBUG
mInitialized = PR_FALSE;
#endif
}
static PRBool DeleteValue(nsHashKey* aKey, void* aValue, void* closure)
{
delete ((nsString*)aValue);
return PR_TRUE;
}
DeviceContextImpl::~DeviceContextImpl()
{
nsCOMPtr<nsIObserverService> obs(do_GetService("@mozilla.org/observer-service;1"));
if (obs)
obs->RemoveObserver(this, "memory-pressure");
if (nsnull != mFontCache)
{
delete mFontCache;
mFontCache = nsnull;
}
if (nsnull != mFontAliasTable) {
mFontAliasTable->Enumerate(DeleteValue);
delete mFontAliasTable;
}
}
NS_IMETHODIMP
DeviceContextImpl::Observe(nsISupports* aSubject, const char* aTopic, const PRUnichar* aSomeData)
{
if (mFontCache && !nsCRT::strcmp(aTopic, "memory-pressure")) {
mFontCache->Compact();
}
return NS_OK;
}
NS_IMETHODIMP DeviceContextImpl::Init(nsNativeWidget aWidget)
{
mWidget = aWidget;
CommonInit();
return NS_OK;
}
void DeviceContextImpl::CommonInit(void)
{
#ifdef NS_DEBUG
NS_ASSERTION(!mInitialized, "device context is initialized twice!");
mInitialized = PR_TRUE;
#endif
// register as a memory-pressure observer to free font resources
// in low-memory situations.
nsCOMPtr<nsIObserverService> obs(do_GetService("@mozilla.org/observer-service;1"));
if (obs)
obs->AddObserver(this, "memory-pressure", PR_TRUE);
}
NS_IMETHODIMP DeviceContextImpl::CreateRenderingContext(nsIView *aView, nsIRenderingContext *&aContext)
{
nsresult rv;
aContext = nsnull;
nsCOMPtr<nsIRenderingContext> pContext;
rv = CreateRenderingContextInstance(*getter_AddRefs(pContext));
if (NS_SUCCEEDED(rv)) {
rv = InitRenderingContext(pContext, aView->GetWidget());
if (NS_SUCCEEDED(rv)) {
aContext = pContext;
NS_ADDREF(aContext);
}
}
return rv;
}
NS_IMETHODIMP DeviceContextImpl::CreateRenderingContext(nsIWidget *aWidget, nsIRenderingContext *&aContext)
{
nsresult rv;
aContext = nsnull;
nsCOMPtr<nsIRenderingContext> pContext;
rv = CreateRenderingContextInstance(*getter_AddRefs(pContext));
if (NS_SUCCEEDED(rv)) {
rv = InitRenderingContext(pContext, aWidget);
if (NS_SUCCEEDED(rv)) {
aContext = pContext;
NS_ADDREF(aContext);
}
}
return rv;
}
NS_IMETHODIMP DeviceContextImpl::CreateRenderingContextInstance(nsIRenderingContext *&aContext)
{
static NS_DEFINE_CID(kRenderingContextCID, NS_RENDERING_CONTEXT_CID);
nsresult rv;
nsCOMPtr<nsIRenderingContext> pContext = do_CreateInstance(kRenderingContextCID, &rv);
if (NS_SUCCEEDED(rv)) {
aContext = pContext;
NS_ADDREF(aContext);
}
return rv;
}
nsresult DeviceContextImpl::InitRenderingContext(nsIRenderingContext *aContext, nsIWidget *aWin)
{
return aContext->Init(this, aWin);
}
NS_IMETHODIMP DeviceContextImpl::CreateFontCache()
{
mFontCache = new nsFontCache();
if (!mFontCache) {
return NS_ERROR_OUT_OF_MEMORY;
}
return mFontCache->Init(this);
}
NS_IMETHODIMP DeviceContextImpl::FontMetricsDeleted(const nsIFontMetrics* aFontMetrics)
{
if (mFontCache) {
mFontCache->FontMetricsDeleted(aFontMetrics);
}
return NS_OK;
}
void
DeviceContextImpl::GetLocaleLangGroup(void)
{
if (!mLocaleLangGroup) {
nsCOMPtr<nsILanguageAtomService> langService;
langService = do_GetService(NS_LANGUAGEATOMSERVICE_CONTRACTID);
if (langService) {
mLocaleLangGroup = langService->GetLocaleLanguageGroup();
}
if (!mLocaleLangGroup) {
mLocaleLangGroup = do_GetAtom("x-western");
}
}
}
NS_IMETHODIMP DeviceContextImpl::GetMetricsFor(const nsFont& aFont,
nsIAtom* aLangGroup, gfxUserFontSet *aUserFontSet, nsIFontMetrics*& aMetrics)
{
if (nsnull == mFontCache) {
nsresult rv = CreateFontCache();
if (NS_FAILED(rv)) {
aMetrics = nsnull;
return rv;
}
// XXX temporary fix for performance problem -- erik
GetLocaleLangGroup();
}
// XXX figure out why aLangGroup is NULL sometimes
if (!aLangGroup) {
aLangGroup = mLocaleLangGroup;
}
return mFontCache->GetMetricsFor(aFont, aLangGroup, aUserFontSet, aMetrics);
}
NS_IMETHODIMP DeviceContextImpl::GetMetricsFor(const nsFont& aFont,
gfxUserFontSet *aUserFontSet,
nsIFontMetrics*& aMetrics)
{
if (nsnull == mFontCache) {
nsresult rv = CreateFontCache();
if (NS_FAILED(rv)) {
aMetrics = nsnull;
return rv;
}
// XXX temporary fix for performance problem -- erik
GetLocaleLangGroup();
}
return mFontCache->GetMetricsFor(aFont, mLocaleLangGroup, aUserFontSet,
aMetrics);
}
NS_IMETHODIMP DeviceContextImpl::GetDepth(PRUint32& aDepth)
{
aDepth = 24;
return NS_OK;
}
NS_IMETHODIMP DeviceContextImpl::GetPaletteInfo(nsPaletteInfo& aPaletteInfo)
{
aPaletteInfo.isPaletteDevice = PR_FALSE;
aPaletteInfo.sizePalette = 0;
aPaletteInfo.numReserved = 0;
aPaletteInfo.palette = nsnull;
return NS_OK;
}
struct FontEnumData {
FontEnumData(nsIDeviceContext* aDC, nsString& aFaceName)
: mDC(aDC), mFaceName(aFaceName)
{}
nsIDeviceContext* mDC;
nsString& mFaceName;
};
static PRBool FontEnumCallback(const nsString& aFamily, PRBool aGeneric, void *aData)
{
FontEnumData* data = (FontEnumData*)aData;
// XXX for now, all generic fonts are presumed to exist
// we may want to actually check if there's an installed conversion
if (aGeneric) {
data->mFaceName = aFamily;
return PR_FALSE; // found one, stop.
}
else {
nsAutoString local;
PRBool aliased;
data->mDC->GetLocalFontName(aFamily, local, aliased);
if (aliased || (NS_SUCCEEDED(data->mDC->CheckFontExistence(local)))) {
data->mFaceName = local;
return PR_FALSE; // found one, stop.
}
}
return PR_TRUE; // didn't exist, continue looking
}
NS_IMETHODIMP DeviceContextImpl::FirstExistingFont(const nsFont& aFont, nsString& aFaceName)
{
FontEnumData data(this, aFaceName);
if (aFont.EnumerateFamilies(FontEnumCallback, &data)) {
return NS_ERROR_FAILURE; // ran out
}
return NS_OK;
}
class FontAliasKey: public nsHashKey
{
public:
FontAliasKey(const nsString& aString)
{mString.Assign(aString);}
virtual PRUint32 HashCode(void) const;
virtual PRBool Equals(const nsHashKey *aKey) const;
virtual nsHashKey *Clone(void) const;
nsString mString;
};
PRUint32 FontAliasKey::HashCode(void) const
{
PRUint32 hash = 0;
const PRUnichar* string = mString.get();
PRUnichar ch;
while ((ch = *string++) != 0) {
// FYI: hash = hash*37 + ch
ch = ToUpperCase(ch);
hash = ((hash << 5) + (hash << 2) + hash) + ch;
}
return hash;
}
PRBool FontAliasKey::Equals(const nsHashKey *aKey) const
{
return mString.Equals(((FontAliasKey*)aKey)->mString, nsCaseInsensitiveStringComparator());
}
nsHashKey* FontAliasKey::Clone(void) const
{
return new FontAliasKey(mString);
}
nsresult DeviceContextImpl::CreateFontAliasTable()
{
nsresult result = NS_OK;
if (nsnull == mFontAliasTable) {
mFontAliasTable = new nsHashtable();
if (nsnull != mFontAliasTable) {
nsAutoString times; times.AssignLiteral("Times");
nsAutoString timesNewRoman; timesNewRoman.AssignLiteral("Times New Roman");
nsAutoString timesRoman; timesRoman.AssignLiteral("Times Roman");
nsAutoString arial; arial.AssignLiteral("Arial");
nsAutoString helvetica; helvetica.AssignLiteral("Helvetica");
nsAutoString courier; courier.AssignLiteral("Courier");
nsAutoString courierNew; courierNew.AssignLiteral("Courier New");
nsAutoString nullStr;
AliasFont(times, timesNewRoman, timesRoman, PR_FALSE);
AliasFont(timesRoman, timesNewRoman, times, PR_FALSE);
AliasFont(timesNewRoman, timesRoman, times, PR_FALSE);
AliasFont(arial, helvetica, nullStr, PR_FALSE);
AliasFont(helvetica, arial, nullStr, PR_FALSE);
AliasFont(courier, courierNew, nullStr, PR_TRUE);
AliasFont(courierNew, courier, nullStr, PR_FALSE);
}
else {
result = NS_ERROR_OUT_OF_MEMORY;
}
}
return result;
}
nsresult DeviceContextImpl::AliasFont(const nsString& aFont,
const nsString& aAlias, const nsString& aAltAlias,
PRBool aForceAlias)
{
nsresult result = NS_OK;
if (nsnull != mFontAliasTable) {
if (aForceAlias || NS_FAILED(CheckFontExistence(aFont))) {
if (NS_SUCCEEDED(CheckFontExistence(aAlias))) {
nsString* entry = new nsString(aAlias);
if (nsnull != entry) {
FontAliasKey key(aFont);
mFontAliasTable->Put(&key, entry);
}
else {
result = NS_ERROR_OUT_OF_MEMORY;
}
}
else if (!aAltAlias.IsEmpty() && NS_SUCCEEDED(CheckFontExistence(aAltAlias))) {
nsString* entry = new nsString(aAltAlias);
if (nsnull != entry) {
FontAliasKey key(aFont);
mFontAliasTable->Put(&key, entry);
}
else {
result = NS_ERROR_OUT_OF_MEMORY;
}
}
}
}
else {
result = NS_ERROR_FAILURE;
}
return result;
}
NS_IMETHODIMP DeviceContextImpl::GetLocalFontName(const nsString& aFaceName, nsString& aLocalName,
PRBool& aAliased)
{
nsresult result = NS_OK;
if (nsnull == mFontAliasTable) {
result = CreateFontAliasTable();
}
if (nsnull != mFontAliasTable) {
FontAliasKey key(aFaceName);
const nsString* alias = (const nsString*)mFontAliasTable->Get(&key);
if (nsnull != alias) {
aLocalName = *alias;
aAliased = PR_TRUE;
}
else {
aLocalName = aFaceName;
aAliased = PR_FALSE;
}
}
return result;
}
NS_IMETHODIMP DeviceContextImpl::FlushFontCache(void)
{
if (nsnull != mFontCache)
mFontCache->Flush();
return NS_OK;
}
/////////////////////////////////////////////////////////////
nsFontCache::nsFontCache()
{
MOZ_COUNT_CTOR(nsFontCache);
mContext = nsnull;
}
nsFontCache::~nsFontCache()
{
MOZ_COUNT_DTOR(nsFontCache);
Flush();
}
nsresult
nsFontCache::Init(nsIDeviceContext* aContext)
{
NS_PRECONDITION(nsnull != aContext, "null ptr");
// Note: we don't hold a reference to the device context, because it
// holds a reference to us and we don't want circular references
mContext = aContext;
return NS_OK;
}
nsresult
nsFontCache::GetDeviceContext(nsIDeviceContext *&aContext) const
{
aContext = mContext;
NS_IF_ADDREF(aContext);
return NS_OK;
}
nsresult
nsFontCache::GetMetricsFor(const nsFont& aFont, nsIAtom* aLangGroup,
gfxUserFontSet *aUserFontSet, nsIFontMetrics *&aMetrics)
{
// First check our cache
// start from the end, which is where we put the most-recent-used element
nsIFontMetrics* fm;
PRInt32 n = mFontMetrics.Count() - 1;
for (PRInt32 i = n; i >= 0; --i) {
fm = static_cast<nsIFontMetrics*>(mFontMetrics[i]);
nsIThebesFontMetrics* tfm = static_cast<nsIThebesFontMetrics*>(fm);
if (fm->Font().Equals(aFont) && tfm->GetUserFontSet() == aUserFontSet) {
nsCOMPtr<nsIAtom> langGroup;
fm->GetLangGroup(getter_AddRefs(langGroup));
if (aLangGroup == langGroup.get()) {
if (i != n) {
// promote it to the end of the cache
mFontMetrics.MoveElement(i, n);
}
tfm->GetThebesFontGroup()->UpdateFontList();
NS_ADDREF(aMetrics = fm);
return NS_OK;
}
}
}
// It's not in the cache. Get font metrics and then cache them.
aMetrics = nsnull;
nsresult rv = CreateFontMetricsInstance(&fm);
if (NS_FAILED(rv)) return rv;
rv = fm->Init(aFont, aLangGroup, mContext, aUserFontSet);
if (NS_SUCCEEDED(rv)) {
// the mFontMetrics list has the "head" at the end, because append is
// cheaper than insert
mFontMetrics.AppendElement(fm);
aMetrics = fm;
NS_ADDREF(aMetrics);
return NS_OK;
}
fm->Destroy();
NS_RELEASE(fm);
// One reason why Init() fails is because the system is running out of resources.
// e.g., on Win95/98 only a very limited number of GDI objects are available.
// Compact the cache and try again.
Compact();
rv = CreateFontMetricsInstance(&fm);
if (NS_FAILED(rv)) return rv;
rv = fm->Init(aFont, aLangGroup, mContext, aUserFontSet);
if (NS_SUCCEEDED(rv)) {
mFontMetrics.AppendElement(fm);
aMetrics = fm;
NS_ADDREF(aMetrics);
return NS_OK;
}
fm->Destroy();
NS_RELEASE(fm);
// could not setup a new one, send an old one (XXX search a "best match"?)
n = mFontMetrics.Count() - 1; // could have changed in Compact()
if (n >= 0) {
aMetrics = static_cast<nsIFontMetrics*>(mFontMetrics[n]);
NS_ADDREF(aMetrics);
return NS_OK;
}
NS_POSTCONDITION(NS_SUCCEEDED(rv), "font metrics should not be null - bug 136248");
return rv;
}
/* PostScript module may override this method to create
* nsIFontMetrics objects with their own classes
*/
nsresult
nsFontCache::CreateFontMetricsInstance(nsIFontMetrics** fm)
{
static NS_DEFINE_CID(kFontMetricsCID, NS_FONT_METRICS_CID);
return CallCreateInstance(kFontMetricsCID, fm);
}
nsresult nsFontCache::FontMetricsDeleted(const nsIFontMetrics* aFontMetrics)
{
mFontMetrics.RemoveElement((void*)aFontMetrics);
return NS_OK;
}
nsresult nsFontCache::Compact()
{
// Need to loop backward because the running element can be removed on the way
for (PRInt32 i = mFontMetrics.Count()-1; i >= 0; --i) {
nsIFontMetrics* fm = static_cast<nsIFontMetrics*>(mFontMetrics[i]);
nsIFontMetrics* oldfm = fm;
// Destroy() isn't here because we want our device context to be notified
NS_RELEASE(fm); // this will reset fm to nsnull
// if the font is really gone, it would have called back in
// FontMetricsDeleted() and would have removed itself
if (mFontMetrics.IndexOf(oldfm) >= 0) {
// nope, the font is still there, so let's hold onto it too
NS_ADDREF(oldfm);
}
}
return NS_OK;
}
nsresult nsFontCache::Flush()
{
for (PRInt32 i = mFontMetrics.Count()-1; i >= 0; --i) {
nsIFontMetrics* fm = static_cast<nsIFontMetrics*>(mFontMetrics[i]);
// Destroy() will unhook our device context from the fm so that we won't
// waste time in triggering the notification of FontMetricsDeleted()
// in the subsequent release
fm->Destroy();
NS_RELEASE(fm);
}
mFontMetrics.Clear();
return NS_OK;
}
NS_IMETHODIMP
DeviceContextImpl::PrepareNativeWidget(nsIWidget *aWidget, void **aOut)
{
return NS_ERROR_NOT_IMPLEMENTED;
}
NS_IMETHODIMP
DeviceContextImpl::ClearCachedSystemFonts()
{
return NS_OK;
}