blob: 0b3bdb22282c77d33a0897dc4a5dc11a3e9445d0 [file] [log] [blame]
/*
* Copyright 2012 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "GrSWMaskHelper.h"
#include "GrCaps.h"
#include "GrContext.h"
#include "batches/GrDrawBatch.h"
#include "GrDrawContext.h"
#include "GrPipelineBuilder.h"
#include "GrShape.h"
#include "SkDistanceFieldGen.h"
#include "batches/GrRectBatchFactory.h"
/*
* Convert a boolean operation into a transfer mode code
*/
static SkXfermode::Mode op_to_mode(SkRegion::Op op) {
static const SkXfermode::Mode modeMap[] = {
SkXfermode::kDstOut_Mode, // kDifference_Op
SkXfermode::kModulate_Mode, // kIntersect_Op
SkXfermode::kSrcOver_Mode, // kUnion_Op
SkXfermode::kXor_Mode, // kXOR_Op
SkXfermode::kClear_Mode, // kReverseDifference_Op
SkXfermode::kSrc_Mode, // kReplace_Op
};
return modeMap[op];
}
/**
* Draw a single rect element of the clip stack into the accumulation bitmap
*/
void GrSWMaskHelper::drawRect(const SkRect& rect, SkRegion::Op op,
bool antiAlias, uint8_t alpha) {
SkPaint paint;
paint.setXfermode(SkXfermode::Make(op_to_mode(op)));
paint.setAntiAlias(antiAlias);
paint.setColor(SkColorSetARGB(alpha, alpha, alpha, alpha));
fDraw.drawRect(rect, paint);
}
/**
* Draw a single path element of the clip stack into the accumulation bitmap
*/
void GrSWMaskHelper::drawShape(const GrShape& shape, SkRegion::Op op, bool antiAlias,
uint8_t alpha) {
SkPaint paint;
paint.setPathEffect(sk_ref_sp(shape.style().pathEffect()));
shape.style().strokeRec().applyToPaint(&paint);
paint.setAntiAlias(antiAlias);
SkPath path;
shape.asPath(&path);
if (SkRegion::kReplace_Op == op && 0xFF == alpha) {
SkASSERT(0xFF == paint.getAlpha());
fDraw.drawPathCoverage(path, paint);
} else {
paint.setXfermodeMode(op_to_mode(op));
paint.setColor(SkColorSetARGB(alpha, alpha, alpha, alpha));
fDraw.drawPath(path, paint);
}
}
bool GrSWMaskHelper::init(const SkIRect& resultBounds, const SkMatrix* matrix) {
if (matrix) {
fMatrix = *matrix;
} else {
fMatrix.setIdentity();
}
// Now translate so the bound's UL corner is at the origin
fMatrix.postTranslate(-SkIntToScalar(resultBounds.fLeft), -SkIntToScalar(resultBounds.fTop));
SkIRect bounds = SkIRect::MakeWH(resultBounds.width(), resultBounds.height());
const SkImageInfo bmImageInfo = SkImageInfo::MakeA8(bounds.width(), bounds.height());
if (!fPixels.tryAlloc(bmImageInfo)) {
return false;
}
fPixels.erase(0);
sk_bzero(&fDraw, sizeof(fDraw));
fDraw.fDst = fPixels;
fRasterClip.setRect(bounds);
fDraw.fRC = &fRasterClip;
fDraw.fMatrix = &fMatrix;
return true;
}
/**
* Get a texture (from the texture cache) of the correct size & format.
*/
GrTexture* GrSWMaskHelper::createTexture() {
GrSurfaceDesc desc;
desc.fWidth = fPixels.width();
desc.fHeight = fPixels.height();
desc.fConfig = kAlpha_8_GrPixelConfig;
return fTexProvider->createApproxTexture(desc);
}
/**
* Move the result of the software mask generation back to the gpu
*/
void GrSWMaskHelper::toTexture(GrTexture *texture) {
// Since we're uploading to it, and it's compressed, 'texture' shouldn't
// have a render target.
SkASSERT(!texture->asRenderTarget());
texture->writePixels(0, 0, fPixels.width(), fPixels.height(), texture->config(),
fPixels.addr(), fPixels.rowBytes());
}
/**
* Convert mask generation results to a signed distance field
*/
void GrSWMaskHelper::toSDF(unsigned char* sdf) {
SkGenerateDistanceFieldFromA8Image(sdf, (const unsigned char*)fPixels.addr(),
fPixels.width(), fPixels.height(), fPixels.rowBytes());
}
////////////////////////////////////////////////////////////////////////////////
/**
* Software rasterizes shape to A8 mask and uploads the result to a scratch texture. Returns the
* resulting texture on success; nullptr on failure.
*/
GrTexture* GrSWMaskHelper::DrawShapeMaskToTexture(GrTextureProvider* texProvider,
const GrShape& shape,
const SkIRect& resultBounds,
bool antiAlias,
const SkMatrix* matrix) {
GrSWMaskHelper helper(texProvider);
if (!helper.init(resultBounds, matrix)) {
return nullptr;
}
helper.drawShape(shape, SkRegion::kReplace_Op, antiAlias, 0xFF);
GrTexture* texture(helper.createTexture());
if (!texture) {
return nullptr;
}
helper.toTexture(texture);
return texture;
}
void GrSWMaskHelper::DrawToTargetWithShapeMask(GrTexture* texture,
GrDrawContext* drawContext,
const GrPaint& paint,
const GrUserStencilSettings* userStencilSettings,
const GrClip& clip,
const SkMatrix& viewMatrix,
const SkIRect& rect) {
SkMatrix invert;
if (!viewMatrix.invert(&invert)) {
return;
}
SkRect dstRect = SkRect::MakeLTRB(SK_Scalar1 * rect.fLeft,
SK_Scalar1 * rect.fTop,
SK_Scalar1 * rect.fRight,
SK_Scalar1 * rect.fBottom);
// We use device coords to compute the texture coordinates. We take the device coords and apply
// a translation so that the top-left of the device bounds maps to 0,0, and then a scaling
// matrix to normalized coords.
SkMatrix maskMatrix;
maskMatrix.setIDiv(texture->width(), texture->height());
maskMatrix.preTranslate(SkIntToScalar(-rect.fLeft), SkIntToScalar(-rect.fTop));
GrPipelineBuilder pipelineBuilder(paint, drawContext->mustUseHWAA(paint));
pipelineBuilder.setUserStencil(userStencilSettings);
pipelineBuilder.addCoverageFragmentProcessor(
GrSimpleTextureEffect::Make(texture,
maskMatrix,
GrTextureParams::kNone_FilterMode,
kDevice_GrCoordSet));
SkAutoTUnref<GrDrawBatch> batch(GrRectBatchFactory::CreateNonAAFill(paint.getColor(),
SkMatrix::I(),
dstRect, nullptr, &invert));
drawContext->drawBatch(pipelineBuilder, clip, batch);
}