SkColorFilterImageFilter.cpp revision 68400767be5f72e4b9750ccc8bcf0078d42869a7
144888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org/* 244888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org * Copyright 2012 The Android Open Source Project 344888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org * 444888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org * Use of this source code is governed by a BSD-style license that can be 544888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org * found in the LICENSE file. 644888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org */ 744888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org 844888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org#include "SkColorFilterImageFilter.h" 944888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org#include "SkBitmap.h" 1044888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org#include "SkCanvas.h" 118d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org#include "SkColorMatrixFilter.h" 1244888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org#include "SkDevice.h" 1344888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org#include "SkColorFilter.h" 1444888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org#include "SkFlattenableBuffers.h" 1544888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org 168d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.orgnamespace { 178d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org 188d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.orgvoid mult_color_matrix(SkScalar a[20], SkScalar b[20], SkScalar out[20]) { 198d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org for (int j = 0; j < 4; ++j) { 208d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org for (int i = 0; i < 5; ++i) { 218d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org out[i+j*5] = 4 == i ? a[4+j*5] : 0; 228d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org for (int k = 0; k < 4; ++k) 238d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org out[i+j*5] += SkScalarMul(a[k+j*5], b[i+k*5]); 248d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org } 258d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org } 268d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org} 278d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org 288d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org// To detect if we need to apply clamping after applying a matrix, we check if 298d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org// any output component might go outside of [0, 255] for any combination of 308d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org// input components in [0..255]. 318d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org// Each output component is an affine transformation of the input component, so 328d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org// the minimum and maximum values are for any combination of minimum or maximum 338d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org// values of input components (i.e. 0 or 255). 348d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org// E.g. if R' = x*R + y*G + z*B + w*A + t 358d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org// Then the maximum value will be for R=255 if x>0 or R=0 if x<0, and the 368d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org// minimum value will be for R=0 if x>0 or R=255 if x<0. 378d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org// Same goes for all components. 388d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.orgbool component_needs_clamping(SkScalar row[5]) { 398d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org SkScalar maxValue = row[4] / 255; 408d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org SkScalar minValue = row[4] / 255; 418d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org for (int i = 0; i < 4; ++i) { 428d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org if (row[i] > 0) 438d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org maxValue += row[i]; 448d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org else 458d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org minValue += row[i]; 468d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org } 478d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org return (maxValue > 1) || (minValue < 0); 488d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org} 498d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org 508d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.orgbool matrix_needs_clamping(SkScalar matrix[20]) { 518d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org return component_needs_clamping(matrix) 528d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org || component_needs_clamping(matrix+5) 538d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org || component_needs_clamping(matrix+10) 548d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org || component_needs_clamping(matrix+15); 558d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org} 568d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org 578d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org}; 588d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org 59cd9f55989e680b7f52fa21766dde0ac67ac9911fsenorblanco@chromium.orgSkColorFilterImageFilter* SkColorFilterImageFilter::Create(SkColorFilter* cf, 60cd9f55989e680b7f52fa21766dde0ac67ac9911fsenorblanco@chromium.org SkImageFilter* input) { 61cd9f55989e680b7f52fa21766dde0ac67ac9911fsenorblanco@chromium.org SkASSERT(cf); 62cd9f55989e680b7f52fa21766dde0ac67ac9911fsenorblanco@chromium.org SkScalar colorMatrix[20], inputMatrix[20]; 63cd9f55989e680b7f52fa21766dde0ac67ac9911fsenorblanco@chromium.org SkColorFilter* inputColorFilter; 64cd9f55989e680b7f52fa21766dde0ac67ac9911fsenorblanco@chromium.org if (input && cf->asColorMatrix(colorMatrix) 65a1c511b8704c6c266b90860a4c68f30ca7514f9bsugoi@google.com && input->asColorFilter(&inputColorFilter) 66a1c511b8704c6c266b90860a4c68f30ca7514f9bsugoi@google.com && (NULL != inputColorFilter)) { 67a1c511b8704c6c266b90860a4c68f30ca7514f9bsugoi@google.com SkAutoUnref autoUnref(inputColorFilter); 68a1c511b8704c6c266b90860a4c68f30ca7514f9bsugoi@google.com if (inputColorFilter->asColorMatrix(inputMatrix) && !matrix_needs_clamping(inputMatrix)) { 69a1c511b8704c6c266b90860a4c68f30ca7514f9bsugoi@google.com SkScalar combinedMatrix[20]; 70a1c511b8704c6c266b90860a4c68f30ca7514f9bsugoi@google.com mult_color_matrix(inputMatrix, colorMatrix, combinedMatrix); 71a1c511b8704c6c266b90860a4c68f30ca7514f9bsugoi@google.com SkAutoTUnref<SkColorFilter> newCF(SkNEW_ARGS(SkColorMatrixFilter, (combinedMatrix))); 72a1c511b8704c6c266b90860a4c68f30ca7514f9bsugoi@google.com return SkNEW_ARGS(SkColorFilterImageFilter, (newCF, input->getInput(0))); 73a1c511b8704c6c266b90860a4c68f30ca7514f9bsugoi@google.com } 74cd9f55989e680b7f52fa21766dde0ac67ac9911fsenorblanco@chromium.org } 75a1c511b8704c6c266b90860a4c68f30ca7514f9bsugoi@google.com return SkNEW_ARGS(SkColorFilterImageFilter, (cf, input)); 76cd9f55989e680b7f52fa21766dde0ac67ac9911fsenorblanco@chromium.org} 77cd9f55989e680b7f52fa21766dde0ac67ac9911fsenorblanco@chromium.org 7844888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.orgSkColorFilterImageFilter::SkColorFilterImageFilter(SkColorFilter* cf, SkImageFilter* input) : INHERITED(input), fColorFilter(cf) { 798d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org SkASSERT(cf); 8044888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org SkSafeRef(cf); 8144888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org} 8244888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org 8344888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.orgSkColorFilterImageFilter::SkColorFilterImageFilter(SkFlattenableReadBuffer& buffer) : INHERITED(buffer) { 8444888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org fColorFilter = buffer.readFlattenableT<SkColorFilter>(); 8544888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org} 8644888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org 8744888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.orgvoid SkColorFilterImageFilter::flatten(SkFlattenableWriteBuffer& buffer) const { 8844888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org this->INHERITED::flatten(buffer); 89fbfcd5602128ec010c82cb733c9cdc0a3254f9f3rmistry@google.com 9044888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org buffer.writeFlattenable(fColorFilter); 9144888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org} 9244888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org 9344888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.orgSkColorFilterImageFilter::~SkColorFilterImageFilter() { 9444888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org SkSafeUnref(fColorFilter); 9544888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org} 9644888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org 9744888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.orgbool SkColorFilterImageFilter::onFilterImage(Proxy* proxy, const SkBitmap& source, 9844888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org const SkMatrix& matrix, 9944888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org SkBitmap* result, 10044888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org SkIPoint* loc) { 10168400767be5f72e4b9750ccc8bcf0078d42869a7senorblanco@chromium.org SkBitmap src = source; 10268400767be5f72e4b9750ccc8bcf0078d42869a7senorblanco@chromium.org if (getInput(0) && !getInput(0)->filterImage(proxy, source, matrix, &src, loc)) { 10368400767be5f72e4b9750ccc8bcf0078d42869a7senorblanco@chromium.org return false; 10468400767be5f72e4b9750ccc8bcf0078d42869a7senorblanco@chromium.org } 10568400767be5f72e4b9750ccc8bcf0078d42869a7senorblanco@chromium.org 10644888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org SkAutoTUnref<SkDevice> device(proxy->createDevice(src.width(), src.height())); 10744888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org SkCanvas canvas(device.get()); 10844888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org SkPaint paint; 10944888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org 11044888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org paint.setXfermodeMode(SkXfermode::kSrc_Mode); 111cd9f55989e680b7f52fa21766dde0ac67ac9911fsenorblanco@chromium.org paint.setColorFilter(fColorFilter); 11244888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org canvas.drawSprite(src, 0, 0, &paint); 11344888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org 11444888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org *result = device.get()->accessBitmap(false); 11544888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org return true; 11644888c66d4bf03da58eb9fbd3db92eb477141aabsenorblanco@chromium.org} 1178d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org 118a1c511b8704c6c266b90860a4c68f30ca7514f9bsugoi@google.combool SkColorFilterImageFilter::asColorFilter(SkColorFilter** filter) const { 119a1c511b8704c6c266b90860a4c68f30ca7514f9bsugoi@google.com if (filter) { 120a1c511b8704c6c266b90860a4c68f30ca7514f9bsugoi@google.com *filter = fColorFilter; 121a1c511b8704c6c266b90860a4c68f30ca7514f9bsugoi@google.com fColorFilter->ref(); 122a1c511b8704c6c266b90860a4c68f30ca7514f9bsugoi@google.com } 123a1c511b8704c6c266b90860a4c68f30ca7514f9bsugoi@google.com return true; 1248d21f6c7a9d0cf4f87d77c235c6da7203620c7e5senorblanco@chromium.org} 125