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/*
* Copyright 2011 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "sk_tool_utils.h"
#include "SampleCode.h"
#include "SkView.h"
#include "SkCanvas.h"
#include "SkColorFilter.h"
#include "SkPaint.h"
#include "SkShader.h"
static int inflate5To8(int x) {
return (x << 3) | (x >> 2);
}
static int trunc5(int x) {
return x >> 3;
}
#define SK_R16_BITS 5
#ifdef SK_DEBUG
static int round5_slow(int x) {
int orig = x & 7;
int fake = x >> 5;
int trunc = x >> 3;
int diff = fake - orig;
int bias = 0;
if (diff > 4) {
bias = -1;
} else if (diff < -4) {
bias = 1;
}
return trunc + bias;
}
#endif
static int round5_fast(int x) {
int result = x + 3 - (x >> 5) + (x >> 7);
result >>= 3;
#ifdef SK_DEBUG
{
int r2 = round5_slow(x);
SkASSERT(r2 == result);
}
#endif
return result;
}
static void test_5bits() {
int e0 = 0;
int e1 = 0;
int e2 = 0;
int ae0 = 0;
int ae1 = 0;
int ae2 = 0;
for (int i = 0; i < 256; i++) {
int t0 = trunc5(i);
int t1 = round5_fast(i);
int t2 = trunc5(i);
int v0 = inflate5To8(t0);
int v1 = inflate5To8(t1);
int v2 = inflate5To8(t2);
int err0 = i - v0;
int err1 = i - v1;
int err2 = i - v2;
SkDebugf("--- %3d : trunc=%3d (%2d) round:%3d (%2d) \n"/*new:%d (%2d)\n"*/, i,
v0, err0, v1, err1, v2, err2);
e0 += err0;
e1 += err1;
e2 += err2;
ae0 += SkAbs32(err0);
ae1 += SkAbs32(err1);
ae2 += SkAbs32(err2);
}
SkDebugf("--- trunc: %d %d round: %d %d new: %d %d\n", e0, ae0, e1, ae1, e2, ae2);
}
static SkBitmap createBitmap(int n) {
SkBitmap bitmap;
bitmap.allocN32Pixels(n, n);
bitmap.eraseColor(SK_ColorTRANSPARENT);
SkCanvas canvas(bitmap);
SkRect r;
r.set(0, 0, SkIntToScalar(n), SkIntToScalar(n));
r.inset(SK_Scalar1, SK_Scalar1);
SkPaint paint;
paint.setAntiAlias(true);
paint.setColor(SK_ColorRED);
canvas.drawOval(r, paint);
r.inset(SK_Scalar1*n/4, SK_Scalar1*n/4);
paint.setBlendMode(SkBlendMode::kSrc);
paint.setColor(0x800000FF);
canvas.drawOval(r, paint);
return bitmap;
}
class ColorFilterView : public SampleView {
SkBitmap fBitmap;
sk_sp<SkShader> fShader;
enum {
N = 64
};
protected:
void onOnceBeforeDraw() override {
fBitmap = createBitmap(N);
fShader = sk_tool_utils::create_checkerboard_shader(
0xFFCCCCCC, 0xFFFFFFFF, 12);
if (false) { // avoid bit rot, suppress warning
test_5bits();
}
}
// overrides from SkEventSink
bool onQuery(SkEvent* evt) override {
if (SampleCode::TitleQ(*evt)) {
SampleCode::TitleR(evt, "ColorFilter");
return true;
}
return this->INHERITED::onQuery(evt);
}
void onDrawBackground(SkCanvas* canvas) override {
SkPaint paint;
paint.setShader(fShader);
canvas->drawPaint(paint);
}
void onDrawContent(SkCanvas* canvas) override {
if (false) {
SkPaint p;
p.setAntiAlias(true);
SkRect r = { 20.4f, 10, 20.6f, 20 };
canvas->drawRect(r, p);
r.set(30.9f, 10, 31.1f, 20);
canvas->drawRect(r, p);
return;
}
static const SkBlendMode gModes[] = {
SkBlendMode::kClear,
SkBlendMode::kSrc,
SkBlendMode::kDst,
SkBlendMode::kSrcOver,
SkBlendMode::kDstOver,
SkBlendMode::kSrcIn,
SkBlendMode::kDstIn,
SkBlendMode::kSrcOut,
SkBlendMode::kDstOut,
SkBlendMode::kSrcATop,
SkBlendMode::kDstATop,
SkBlendMode::kXor,
SkBlendMode::kPlus,
SkBlendMode::kModulate,
};
static const SkColor gColors[] = {
0xFF000000,
0x80000000,
0xFF00FF00,
0x8000FF00,
0x00000000,
};
float scale = 1.5f;
SkPaint paint;
canvas->translate(N / 8, N / 8);
for (size_t y = 0; y < SK_ARRAY_COUNT(gColors); y++) {
for (size_t x = 0; x < SK_ARRAY_COUNT(gModes); x++) {
paint.setColorFilter(SkColorFilter::MakeModeFilter(gColors[y], gModes[x]));
canvas->drawBitmap(fBitmap, x * N * 1.25f, y * N * scale, &paint);
}
}
}
private:
typedef SampleView INHERITED;
};
//////////////////////////////////////////////////////////////////////////////
static SkView* MyFactory() { return new ColorFilterView; }
static SkViewRegister reg(MyFactory);
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