layout/svg/nsSVGMaskFrame.cpp@6474c204b198
layout/svg/nsSVGMaskFrame.cpp
Wed, 31 Dec 2014 06:09:35 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Wed, 31 Dec 2014 06:09:35 +0100
- changeset 0
- 6474c204b198
- permissions
- -rw-r--r--
Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.
1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
2 /* This Source Code Form is subject to the terms of the Mozilla Public
3 * License, v. 2.0. If a copy of the MPL was not distributed with this
4 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
6 // Main header first:
7 #include "nsSVGMaskFrame.h"
9 // Keep others in (case-insensitive) order:
10 #include "gfxContext.h"
11 #include "gfxImageSurface.h"
12 #include "nsRenderingContext.h"
13 #include "nsSVGEffects.h"
14 #include "mozilla/dom/SVGMaskElement.h"
16 using namespace mozilla::dom;
18 /**
19 * Byte offsets of channels in a native packed gfxColor or cairo image surface.
20 */
21 #ifdef IS_BIG_ENDIAN
22 #define GFX_ARGB32_OFFSET_A 0
23 #define GFX_ARGB32_OFFSET_R 1
24 #define GFX_ARGB32_OFFSET_G 2
25 #define GFX_ARGB32_OFFSET_B 3
26 #else
27 #define GFX_ARGB32_OFFSET_A 3
28 #define GFX_ARGB32_OFFSET_R 2
29 #define GFX_ARGB32_OFFSET_G 1
30 #define GFX_ARGB32_OFFSET_B 0
31 #endif
33 // c = n / 255
34 // c <= 0.04045 ? c / 12.92 : pow((c + 0.055) / 1.055, 2.4)) * 255 + 0.5
35 static const uint8_t gsRGBToLinearRGBMap[256] = {
36 0, 0, 0, 0, 0, 0, 0, 1,
37 1, 1, 1, 1, 1, 1, 1, 1,
38 1, 1, 2, 2, 2, 2, 2, 2,
39 2, 2, 3, 3, 3, 3, 3, 3,
40 4, 4, 4, 4, 4, 5, 5, 5,
41 5, 6, 6, 6, 6, 7, 7, 7,
42 8, 8, 8, 8, 9, 9, 9, 10,
43 10, 10, 11, 11, 12, 12, 12, 13,
44 13, 13, 14, 14, 15, 15, 16, 16,
45 17, 17, 17, 18, 18, 19, 19, 20,
46 20, 21, 22, 22, 23, 23, 24, 24,
47 25, 25, 26, 27, 27, 28, 29, 29,
48 30, 30, 31, 32, 32, 33, 34, 35,
49 35, 36, 37, 37, 38, 39, 40, 41,
50 41, 42, 43, 44, 45, 45, 46, 47,
51 48, 49, 50, 51, 51, 52, 53, 54,
52 55, 56, 57, 58, 59, 60, 61, 62,
53 63, 64, 65, 66, 67, 68, 69, 70,
54 71, 72, 73, 74, 76, 77, 78, 79,
55 80, 81, 82, 84, 85, 86, 87, 88,
56 90, 91, 92, 93, 95, 96, 97, 99,
57 100, 101, 103, 104, 105, 107, 108, 109,
58 111, 112, 114, 115, 116, 118, 119, 121,
59 122, 124, 125, 127, 128, 130, 131, 133,
60 134, 136, 138, 139, 141, 142, 144, 146,
61 147, 149, 151, 152, 154, 156, 157, 159,
62 161, 163, 164, 166, 168, 170, 171, 173,
63 175, 177, 179, 181, 183, 184, 186, 188,
64 190, 192, 194, 196, 198, 200, 202, 204,
65 206, 208, 210, 212, 214, 216, 218, 220,
66 222, 224, 226, 229, 231, 233, 235, 237,
67 239, 242, 244, 246, 248, 250, 253, 255
68 };
70 static void
71 ComputesRGBLuminanceMask(uint8_t *aData,
72 int32_t aStride,
73 const nsIntRect &aRect,
74 float aOpacity)
75 {
76 for (int32_t y = aRect.y; y < aRect.YMost(); y++) {
77 for (int32_t x = aRect.x; x < aRect.XMost(); x++) {
78 uint8_t *pixel = aData + aStride * y + 4 * x;
79 uint8_t a = pixel[GFX_ARGB32_OFFSET_A];
81 uint8_t luminance;
82 if (a) {
83 /* sRGB -> intensity (unpremultiply cancels out the
84 * (a/255.0) multiplication with aOpacity */
85 luminance =
86 static_cast<uint8_t>
87 ((pixel[GFX_ARGB32_OFFSET_R] * 0.2125 +
88 pixel[GFX_ARGB32_OFFSET_G] * 0.7154 +
89 pixel[GFX_ARGB32_OFFSET_B] * 0.0721) *
90 aOpacity);
91 } else {
92 luminance = 0;
93 }
94 memset(pixel, luminance, 4);
95 }
96 }
97 }
99 static void
100 ComputeLinearRGBLuminanceMask(uint8_t *aData,
101 int32_t aStride,
102 const nsIntRect &aRect,
103 float aOpacity)
104 {
105 for (int32_t y = aRect.y; y < aRect.YMost(); y++) {
106 for (int32_t x = aRect.x; x < aRect.XMost(); x++) {
107 uint8_t *pixel = aData + aStride * y + 4 * x;
108 uint8_t a = pixel[GFX_ARGB32_OFFSET_A];
110 uint8_t luminance;
111 // unpremultiply
112 if (a) {
113 if (a != 255) {
114 pixel[GFX_ARGB32_OFFSET_B] =
115 (255 * pixel[GFX_ARGB32_OFFSET_B]) / a;
116 pixel[GFX_ARGB32_OFFSET_G] =
117 (255 * pixel[GFX_ARGB32_OFFSET_G]) / a;
118 pixel[GFX_ARGB32_OFFSET_R] =
119 (255 * pixel[GFX_ARGB32_OFFSET_R]) / a;
120 }
122 /* sRGB -> linearRGB -> intensity */
123 luminance =
124 static_cast<uint8_t>
125 ((gsRGBToLinearRGBMap[pixel[GFX_ARGB32_OFFSET_R]] *
126 0.2125 +
127 gsRGBToLinearRGBMap[pixel[GFX_ARGB32_OFFSET_G]] *
128 0.7154 +
129 gsRGBToLinearRGBMap[pixel[GFX_ARGB32_OFFSET_B]] *
130 0.0721) * (a / 255.0) * aOpacity);
131 } else {
132 luminance = 0;
133 }
134 memset(pixel, luminance, 4);
135 }
136 }
137 }
139 static void
140 ComputeAlphaMask(uint8_t *aData,
141 int32_t aStride,
142 const nsIntRect &aRect,
143 float aOpacity)
144 {
145 for (int32_t y = aRect.y; y < aRect.YMost(); y++) {
146 for (int32_t x = aRect.x; x < aRect.XMost(); x++) {
147 uint8_t *pixel = aData + aStride * y + 4 * x;
148 uint8_t luminance = pixel[GFX_ARGB32_OFFSET_A] * aOpacity;
149 memset(pixel, luminance, 4);
150 }
151 }
152 }
154 //----------------------------------------------------------------------
155 // Implementation
157 nsIFrame*
158 NS_NewSVGMaskFrame(nsIPresShell* aPresShell, nsStyleContext* aContext)
159 {
160 return new (aPresShell) nsSVGMaskFrame(aContext);
161 }
163 NS_IMPL_FRAMEARENA_HELPERS(nsSVGMaskFrame)
165 already_AddRefed<gfxPattern>
166 nsSVGMaskFrame::ComputeMaskAlpha(nsRenderingContext *aContext,
167 nsIFrame* aParent,
168 const gfxMatrix &aMatrix,
169 float aOpacity)
170 {
171 // If the flag is set when we get here, it means this mask frame
172 // has already been used painting the current mask, and the document
173 // has a mask reference loop.
174 if (mInUse) {
175 NS_WARNING("Mask loop detected!");
176 return nullptr;
177 }
178 AutoMaskReferencer maskRef(this);
180 SVGMaskElement *mask = static_cast<SVGMaskElement*>(mContent);
182 uint16_t units =
183 mask->mEnumAttributes[SVGMaskElement::MASKUNITS].GetAnimValue();
184 gfxRect bbox;
185 if (units == SVG_UNIT_TYPE_OBJECTBOUNDINGBOX) {
186 bbox = nsSVGUtils::GetBBox(aParent);
187 }
189 gfxRect maskArea = nsSVGUtils::GetRelativeRect(units,
190 &mask->mLengthAttributes[SVGMaskElement::ATTR_X], bbox, aParent);
192 gfxContext *gfx = aContext->ThebesContext();
194 // Get the clip extents in device space:
195 gfx->Save();
196 nsSVGUtils::SetClipRect(gfx, aMatrix, maskArea);
197 gfx->IdentityMatrix();
198 gfxRect clipExtents = gfx->GetClipExtents();
199 clipExtents.RoundOut();
200 gfx->Restore();
202 bool resultOverflows;
203 gfxIntSize surfaceSize =
204 nsSVGUtils::ConvertToSurfaceSize(gfxSize(clipExtents.Width(),
205 clipExtents.Height()),
206 &resultOverflows);
208 // 0 disables mask, < 0 is an error
209 if (surfaceSize.width <= 0 || surfaceSize.height <= 0)
210 return nullptr;
212 if (resultOverflows)
213 return nullptr;
215 nsRefPtr<gfxImageSurface> image =
216 new gfxImageSurface(surfaceSize, gfxImageFormat::ARGB32);
217 if (!image || image->CairoStatus())
218 return nullptr;
220 // We would like to use gfxImageSurface::SetDeviceOffset() to position
221 // 'image'. However, we need to set the same matrix on the temporary context
222 // and pattern that we create below as is currently set on 'gfx'.
223 // Unfortunately, any device offset set by SetDeviceOffset() is affected by
224 // the transform passed to the SetMatrix() calls, so to avoid that we account
225 // for the device offset in the transform rather than use SetDeviceOffset().
226 gfxMatrix matrix =
227 gfx->CurrentMatrix() * gfxMatrix().Translate(-clipExtents.TopLeft());
229 nsRefPtr<nsRenderingContext> tmpCtx(new nsRenderingContext);
230 tmpCtx->Init(this->PresContext()->DeviceContext(), image);
231 tmpCtx->ThebesContext()->SetMatrix(matrix);
233 mMaskParent = aParent;
234 if (mMaskParentMatrix) {
235 *mMaskParentMatrix = aMatrix;
236 } else {
237 mMaskParentMatrix = new gfxMatrix(aMatrix);
238 }
240 for (nsIFrame* kid = mFrames.FirstChild(); kid;
241 kid = kid->GetNextSibling()) {
242 // The CTM of each frame referencing us can be different
243 nsISVGChildFrame* SVGFrame = do_QueryFrame(kid);
244 if (SVGFrame) {
245 SVGFrame->NotifySVGChanged(nsISVGChildFrame::TRANSFORM_CHANGED);
246 }
247 nsSVGUtils::PaintFrameWithEffects(tmpCtx, nullptr, kid);
248 }
250 uint8_t *data = image->Data();
251 int32_t stride = image->Stride();
252 nsIntRect rect(0, 0, surfaceSize.width, surfaceSize.height);
254 if (StyleSVGReset()->mMaskType == NS_STYLE_MASK_TYPE_LUMINANCE) {
255 if (StyleSVG()->mColorInterpolation ==
256 NS_STYLE_COLOR_INTERPOLATION_LINEARRGB) {
257 ComputeLinearRGBLuminanceMask(data, stride, rect, aOpacity);
258 } else {
259 ComputesRGBLuminanceMask(data, stride, rect, aOpacity);
260 }
261 } else {
262 ComputeAlphaMask(data, stride, rect, aOpacity);
263 }
265 nsRefPtr<gfxPattern> retval = new gfxPattern(image);
266 retval->SetMatrix(matrix);
267 return retval.forget();
268 }
270 nsresult
271 nsSVGMaskFrame::AttributeChanged(int32_t aNameSpaceID,
272 nsIAtom* aAttribute,
273 int32_t aModType)
274 {
275 if (aNameSpaceID == kNameSpaceID_None &&
276 (aAttribute == nsGkAtoms::x ||
277 aAttribute == nsGkAtoms::y ||
278 aAttribute == nsGkAtoms::width ||
279 aAttribute == nsGkAtoms::height||
280 aAttribute == nsGkAtoms::maskUnits ||
281 aAttribute == nsGkAtoms::maskContentUnits)) {
282 nsSVGEffects::InvalidateDirectRenderingObservers(this);
283 }
285 return nsSVGMaskFrameBase::AttributeChanged(aNameSpaceID,
286 aAttribute, aModType);
287 }
289 #ifdef DEBUG
290 void
291 nsSVGMaskFrame::Init(nsIContent* aContent,
292 nsIFrame* aParent,
293 nsIFrame* aPrevInFlow)
294 {
295 NS_ASSERTION(aContent->IsSVG(nsGkAtoms::mask),
296 "Content is not an SVG mask");
298 nsSVGMaskFrameBase::Init(aContent, aParent, aPrevInFlow);
299 }
300 #endif /* DEBUG */
302 nsIAtom *
303 nsSVGMaskFrame::GetType() const
304 {
305 return nsGkAtoms::svgMaskFrame;
306 }
308 gfxMatrix
309 nsSVGMaskFrame::GetCanvasTM(uint32_t aFor, nsIFrame* aTransformRoot)
310 {
311 NS_ASSERTION(mMaskParentMatrix, "null parent matrix");
313 SVGMaskElement *mask = static_cast<SVGMaskElement*>(mContent);
315 return nsSVGUtils::AdjustMatrixForUnits(
316 mMaskParentMatrix ? *mMaskParentMatrix : gfxMatrix(),
317 &mask->mEnumAttributes[SVGMaskElement::MASKCONTENTUNITS],
318 mMaskParent);
319 }
