/src/skia/include/core/SkUnPreMultiply.h

Source (jump to first uncovered line)

/*
 * Copyright 2008 The Android Open Source Project
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */
#ifndef SkUnPreMultiply_DEFINED
#define SkUnPreMultiply_DEFINED

#include "include/core/SkColor.h"
#include "include/core/SkTypes.h"
#include "include/private/base/SkCPUTypes.h"

#include <cstdint>

class SK_API SkUnPreMultiply {
public:
    typedef uint32_t Scale;

    // index this table with alpha [0..255]
    static const Scale* GetScaleTable() {
        return gTable;
    }

    static Scale GetScale(U8CPU alpha) {
        SkASSERT(alpha <= 255);
        return gTable[alpha];
    }

    /** Usage:

        const Scale* table = SkUnPreMultiply::GetScaleTable();

        for (...) {
            unsigned a = ...
            SkUnPreMultiply::Scale scale = table[a];

            red = SkUnPreMultiply::ApplyScale(scale, red);
            ...
            // now red is unpremultiplied
        }
    */
    static U8CPU ApplyScale(Scale scale, U8CPU component) {
        SkASSERT(component <= 255);
        return (scale * component + (1 << 23)) >> 24;
    }

    static SkColor PMColorToColor(SkPMColor c);

private:
    static const uint32_t gTable[256];
};

#endif

Coverage Report

Created: 2024-05-20 07:14

Line	Count	Source (jump to first uncovered line)
1
2		/*
3		* Copyright 2008 The Android Open Source Project
4		*
5		* Use of this source code is governed by a BSD-style license that can be
6		* found in the LICENSE file.
7		*/
8		#ifndef SkUnPreMultiply_DEFINED
9		#define SkUnPreMultiply_DEFINED
10
11		#include "include/core/SkColor.h"
12		#include "include/core/SkTypes.h"
13		#include "include/private/base/SkCPUTypes.h"
14
15		#include <cstdint>
16
17		class SK_API SkUnPreMultiply {
18		public:
19		typedef uint32_t Scale;
20
21		// index this table with alpha [0..255]
22	0	static const Scale* GetScaleTable() {
23	0	return gTable;
24	0	}
25
26	0	static Scale GetScale(U8CPU alpha) {
27	0	SkASSERT(alpha <= 255);
28	0	return gTable[alpha];
29	0	} Unexecuted instantiation: SkUnPreMultiply::GetScale(unsigned int) Unexecuted instantiation: SkUnPreMultiply::GetScale(unsigned int)
30
31		/** Usage:
32
33		const Scale* table = SkUnPreMultiply::GetScaleTable();
34
35		for (...) {
36		unsigned a = ...
37		SkUnPreMultiply::Scale scale = table[a];
38
39		red = SkUnPreMultiply::ApplyScale(scale, red);
40		...
41		// now red is unpremultiplied
42		}
43		*/
44	0	static U8CPU ApplyScale(Scale scale, U8CPU component) {
45	0	SkASSERT(component <= 255);
46	0	return (scale * component + (1 << 23)) >> 24;
47	0	} Unexecuted instantiation: SkUnPreMultiply::ApplyScale(unsigned int, unsigned int) Unexecuted instantiation: SkUnPreMultiply::ApplyScale(unsigned int, unsigned int)
48
49		static SkColor PMColorToColor(SkPMColor c);
50
51		private:
52		static const uint32_t gTable[256];
53		};
54
55		#endif