/*
* Copyright 2015 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "SkBitmap.h"
#include "SkBlendMode.h"
#include "SkCanvas.h"
#include "SkColor.h"
#include "SkColorSpace.h"
#include "SkImageInfo.h"
#include "SkPaint.h"
#include "SkPoint.h"
#include "SkRect.h"
#include "SkRefCnt.h"
#include "SkSurface.h"
#include "SkTypes.h"
#include "Test.h"
#include "GrBackendSurface.h"
#include "GrContext.h"
#include "GrContextFactory.h"
#include "GrContextPriv.h"
#include "GrResourceProvider.h"
#include "GrTexture.h"
#include "GrTypes.h"
#include <vector>
struct Results { int diffs, diffs_0x00, diffs_0xff, diffs_by_1; };
static bool acceptable(const Results& r) {
#if 0
SkDebugf("%d diffs, %d at 0x00, %d at 0xff, %d off by 1, all out of 65536\n",
r.diffs, r.diffs_0x00, r.diffs_0xff, r.diffs_by_1);
#endif
return r.diffs_by_1 == r.diffs // never off by more than 1
&& r.diffs_0x00 == 0 // transparent must stay transparent
&& r.diffs_0xff == 0; // opaque must stay opaque
}
template <typename Fn>
static Results test(Fn&& multiply) {
Results r = { 0,0,0,0 };
for (int x = 0; x < 256; x++) {
for (int y = 0; y < 256; y++) {
int p = multiply(x, y),
ideal = (x*y+127)/255;
if (p != ideal) {
r.diffs++;
if (x == 0x00 || y == 0x00) { r.diffs_0x00++; }
if (x == 0xff || y == 0xff) { r.diffs_0xff++; }
if (SkTAbs(ideal - p) == 1) { r.diffs_by_1++; }
}
}}
return r;
}
DEF_TEST(Blend_byte_multiply, r) {
// These are all temptingly close but fundamentally broken.
int (*broken[])(int, int) = {
[](int x, int y) { return (x*y)>>8; },
[](int x, int y) { return (x*y+128)>>8; },
[](int x, int y) { y += y>>7; return (x*y)>>8; },
};
for (auto multiply : broken) { REPORTER_ASSERT(r, !acceptable(test(multiply))); }
// These are fine to use, but not perfect.
int (*fine[])(int, int) = {
[](int x, int y) { return (x*y+x)>>8; },
[](int x, int y) { return (x*y+y)>>8; },
[](int x, int y) { return (x*y+255)>>8; },
[](int x, int y) { y += y>>7; return (x*y+128)>>8; },
};
for (auto multiply : fine) { REPORTER_ASSERT(r, acceptable(test(multiply))); }
// These are pefect.
int (*perfect[])(int, int) = {
[](int x, int y) { return (x*y+127)/255; }, // Duh.
[](int x, int y) { int p = (x*y+128); return (p+(p>>8))>>8; },
[](int x, int y) { return ((x*y+128)*257)>>16; },
};
for (auto multiply : perfect) { REPORTER_ASSERT(r, test(multiply).diffs == 0); }
}
namespace {
static sk_sp<SkSurface> create_gpu_surface_backend_texture_as_render_target(
GrContext* context, int sampleCnt, int width, int height, SkColorType colorType,
GrPixelConfig config, GrSurfaceOrigin origin,
sk_sp<GrTexture>* backingSurface) {
GrSurfaceDesc backingDesc;
backingDesc.fFlags = kRenderTarget_GrSurfaceFlag;
backingDesc.fWidth = width;
backingDesc.fHeight = height;
backingDesc.fConfig = config;
backingDesc.fSampleCnt = sampleCnt;
auto resourceProvider = context->priv().resourceProvider();
*backingSurface = resourceProvider->createTexture(backingDesc, SkBudgeted::kNo);
if (!(*backingSurface)) {
return nullptr;
}
GrBackendTexture backendTex = (*backingSurface)->getBackendTexture();
sk_sp<SkSurface> surface =
SkSurface::MakeFromBackendTextureAsRenderTarget(context, backendTex, origin,
sampleCnt, colorType, nullptr, nullptr);
return surface;
}
}
// Tests blending to a surface with no texture available.
DEF_GPUTEST_FOR_GL_RENDERING_CONTEXTS(ES2BlendWithNoTexture, reporter, ctxInfo) {
GrContext* context = ctxInfo.grContext();
const int kWidth = 10;
const int kHeight = 10;
const GrPixelConfig kConfig = kRGBA_8888_GrPixelConfig;
const SkColorType kColorType = kRGBA_8888_SkColorType;
// Build our test cases:
struct RectAndSamplePoint {
SkRect rect;
SkIPoint outPoint;
SkIPoint inPoint;
} allRectsAndPoints[3] = {
{SkRect::MakeXYWH(0, 0, 5, 5), SkIPoint::Make(7, 7), SkIPoint::Make(2, 2)},
{SkRect::MakeXYWH(2, 2, 5, 5), SkIPoint::Make(1, 1), SkIPoint::Make(4, 4)},
{SkRect::MakeXYWH(5, 5, 5, 5), SkIPoint::Make(2, 2), SkIPoint::Make(7, 7)},
};
struct TestCase {
RectAndSamplePoint fRectAndPoints;
SkRect fClip;
int fSampleCnt;
GrSurfaceOrigin fOrigin;
};
std::vector<TestCase> testCases;
for (auto origin : { kTopLeft_GrSurfaceOrigin, kBottomLeft_GrSurfaceOrigin}) {
for (int sampleCnt : {1, 4}) {
for (auto rectAndPoints : allRectsAndPoints) {
for (auto clip : {SkRect::MakeXYWH(0, 0, 10, 10), SkRect::MakeXYWH(1, 1, 8, 8)}) {
testCases.push_back({rectAndPoints, clip, sampleCnt, origin});
}
}
}
}
// Run each test case:
for (auto testCase : testCases) {
int sampleCnt = testCase.fSampleCnt;
SkRect paintRect = testCase.fRectAndPoints.rect;
SkIPoint outPoint = testCase.fRectAndPoints.outPoint;
SkIPoint inPoint = testCase.fRectAndPoints.inPoint;
GrSurfaceOrigin origin = testCase.fOrigin;
sk_sp<GrTexture> backingSurface;
// BGRA forces a framebuffer blit on ES2.
sk_sp<SkSurface> surface = create_gpu_surface_backend_texture_as_render_target(
context, sampleCnt, kWidth, kHeight, kColorType, kConfig, origin, &backingSurface);
if (!surface && sampleCnt > 1) {
// Some platforms don't support MSAA.
continue;
}
REPORTER_ASSERT(reporter, !!surface);
// Fill our canvas with 0xFFFF80
SkCanvas* canvas = surface->getCanvas();
canvas->clipRect(testCase.fClip, false);
SkPaint black_paint;
black_paint.setColor(SkColorSetRGB(0xFF, 0xFF, 0x80));
canvas->drawRect(SkRect::MakeXYWH(0, 0, kWidth, kHeight), black_paint);
// Blend 2x2 pixels at 5,5 with 0x80FFFF. Use multiply blend mode as this will trigger
// a copy of the destination.
SkPaint white_paint;
white_paint.setColor(SkColorSetRGB(0x80, 0xFF, 0xFF));
white_paint.setBlendMode(SkBlendMode::kMultiply);
canvas->drawRect(paintRect, white_paint);
// Read the result into a bitmap.
SkBitmap bitmap;
REPORTER_ASSERT(reporter, bitmap.tryAllocPixels(SkImageInfo::Make(
kWidth, kHeight, kColorType, kPremul_SkAlphaType)));
REPORTER_ASSERT(
reporter,
surface->readPixels(bitmap.info(), bitmap.getPixels(), bitmap.rowBytes(), 0, 0));
// Check the in/out pixels.
REPORTER_ASSERT(reporter, bitmap.getColor(outPoint.x(), outPoint.y()) ==
SkColorSetRGB(0xFF, 0xFF, 0x80));
REPORTER_ASSERT(reporter, bitmap.getColor(inPoint.x(), inPoint.y()) ==
SkColorSetRGB(0x80, 0xFF, 0x80));
// Clean up - surface depends on backingSurface and must be released first.
surface.reset();
backingSurface.reset();
}
}