xref: /aosp_15_r20/external/skia/src/pdf/SkPDFShader.h (revision c8dee2aa9b3f27cf6c858bd81872bdeb2c07ed17)
1 /*
2  * Copyright 2011 Google Inc.
3  *
4  * Use of this source code is governed by a BSD-style license that can be
5  * found in the LICENSE file.
6  */
7 #ifndef SkPDFShader_DEFINED
8 #define SkPDFShader_DEFINED
9 
10 #include "include/core/SkColor.h"
11 #include "include/core/SkMatrix.h"
12 #include "include/core/SkRect.h"
13 #include "include/private/base/SkAssert.h"
14 #include "include/private/base/SkMacros.h"
15 #include "src/core/SkChecksum.h"
16 #include "src/pdf/SkBitmapKey.h"
17 #include "src/pdf/SkPDFTypes.h"
18 
19 class SkPDFDocument;
20 class SkShader;
21 enum class SkTileMode;
22 
23 /** Make a PDF shader for the passed SkShader. If the SkShader is invalid in
24  *  some way, returns nullptr.
25  *
26  *  In PDF parlance, this is a pattern, used in place of a color when the
27  *  pattern color space is selected.
28  *
29  *  May cache the shader in the document for later re-use.  If this function is
30  *  called again with an equivalent shader,  a new reference to the cached pdf
31  *  shader may be returned.
32  *
33  *  @param doc         The parent document, must be non-null.
34  *  @param shader      The SkShader to emulate.
35  *  @param ctm         The current transform matrix. (PDF shaders are absolutely
36  *                     positioned, relative to where the page is drawn.)
37  *  @param surfaceBBox The bounding box of the drawing surface (with matrix
38  *                     already applied).
39  *  @param paintColor  Color+Alpha of the paint.  Color is usually ignored,
40  *                     unless it is a alpha shader.
41  */
42 SkPDFIndirectReference SkPDFMakeShader(SkPDFDocument* doc,
43                                        SkShader* shader,
44                                        const SkMatrix& ctm,
45                                        const SkIRect& surfaceBBox,
46                                        SkColor4f paintColor);
47 
48 SK_BEGIN_REQUIRE_DENSE
49 struct SkPDFImageShaderKey {
50     SkMatrix fTransform;
51     SkIRect fBBox;
52     SkBitmapKey fBitmapKey;
53     SkTileMode fImageTileModes[2];
54     SkColor4f fPaintColor;
55 
56     using Hash = SkForceDirectHash<SkPDFImageShaderKey>;
57 };
58 SK_END_REQUIRE_DENSE
59 
60 inline bool operator==(const SkPDFImageShaderKey& a, const SkPDFImageShaderKey& b) {
61     SkASSERT(a.fBitmapKey.fID != 0);
62     SkASSERT(b.fBitmapKey.fID != 0);
63     return a.fTransform         == b.fTransform
64         && a.fBBox              == b.fBBox
65         && a.fBitmapKey         == b.fBitmapKey
66         && a.fImageTileModes[0] == b.fImageTileModes[0]
67         && a.fImageTileModes[1] == b.fImageTileModes[1]
68         && a.fPaintColor        == b.fPaintColor;
69 }
70 #endif
71