1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/gfx/skia/trunk/src/gpu/GrClipMaskCache.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,235 @@
1.4 +/*
1.5 + * Copyright 2012 Google Inc.
1.6 + *
1.7 + * Use of this source code is governed by a BSD-style license that can be
1.8 + * found in the LICENSE file.
1.9 + */
1.10 +
1.11 +#ifndef GrClipMaskCache_DEFINED
1.12 +#define GrClipMaskCache_DEFINED
1.13 +
1.14 +#include "GrContext.h"
1.15 +#include "SkClipStack.h"
1.16 +#include "SkTypes.h"
1.17 +
1.18 +class GrTexture;
1.19 +
1.20 +/**
1.21 + * The stencil buffer stores the last clip path - providing a single entry
1.22 + * "cache". This class provides similar functionality for AA clip paths
1.23 + */
1.24 +class GrClipMaskCache : public SkNoncopyable {
1.25 +public:
1.26 + GrClipMaskCache();
1.27 +
1.28 + ~GrClipMaskCache() {
1.29 +
1.30 + while (!fStack.empty()) {
1.31 + GrClipStackFrame* temp = (GrClipStackFrame*) fStack.back();
1.32 + temp->~GrClipStackFrame();
1.33 + fStack.pop_back();
1.34 + }
1.35 + }
1.36 +
1.37 + bool canReuse(int32_t clipGenID, const SkIRect& bounds) {
1.38 +
1.39 + SkASSERT(clipGenID != SkClipStack::kWideOpenGenID);
1.40 + SkASSERT(clipGenID != SkClipStack::kEmptyGenID);
1.41 +
1.42 + GrClipStackFrame* back = (GrClipStackFrame*) fStack.back();
1.43 +
1.44 + // We could reuse the mask if bounds is a subset of last bounds. We'd have to communicate
1.45 + // an offset to the caller.
1.46 + if (back->fLastMask.texture() &&
1.47 + back->fLastBound == bounds &&
1.48 + back->fLastClipGenID == clipGenID) {
1.49 + return true;
1.50 + }
1.51 +
1.52 + return false;
1.53 + }
1.54 +
1.55 + void reset() {
1.56 + if (fStack.empty()) {
1.57 +// SkASSERT(false);
1.58 + return;
1.59 + }
1.60 +
1.61 + GrClipStackFrame* back = (GrClipStackFrame*) fStack.back();
1.62 +
1.63 + back->reset();
1.64 + }
1.65 +
1.66 + /**
1.67 + * After a "push" the clip state is entirely open. Currently, the
1.68 + * entire clip stack will be re-rendered into a new clip mask.
1.69 + * TODO: can we take advantage of the nested nature of the clips to
1.70 + * reduce the mask creation cost?
1.71 + */
1.72 + void push();
1.73 +
1.74 + void pop() {
1.75 + //SkASSERT(!fStack.empty());
1.76 +
1.77 + if (!fStack.empty()) {
1.78 + GrClipStackFrame* back = (GrClipStackFrame*) fStack.back();
1.79 +
1.80 + back->~GrClipStackFrame();
1.81 + fStack.pop_back();
1.82 + }
1.83 + }
1.84 +
1.85 + int32_t getLastClipGenID() const {
1.86 +
1.87 + if (fStack.empty()) {
1.88 + return SkClipStack::kInvalidGenID;
1.89 + }
1.90 +
1.91 + return ((GrClipStackFrame*) fStack.back())->fLastClipGenID;
1.92 + }
1.93 +
1.94 + GrTexture* getLastMask() {
1.95 +
1.96 + if (fStack.empty()) {
1.97 + SkASSERT(false);
1.98 + return NULL;
1.99 + }
1.100 +
1.101 + GrClipStackFrame* back = (GrClipStackFrame*) fStack.back();
1.102 +
1.103 + return back->fLastMask.texture();
1.104 + }
1.105 +
1.106 + const GrTexture* getLastMask() const {
1.107 +
1.108 + if (fStack.empty()) {
1.109 + SkASSERT(false);
1.110 + return NULL;
1.111 + }
1.112 +
1.113 + GrClipStackFrame* back = (GrClipStackFrame*) fStack.back();
1.114 +
1.115 + return back->fLastMask.texture();
1.116 + }
1.117 +
1.118 + void acquireMask(int32_t clipGenID,
1.119 + const GrTextureDesc& desc,
1.120 + const SkIRect& bound) {
1.121 +
1.122 + if (fStack.empty()) {
1.123 + SkASSERT(false);
1.124 + return;
1.125 + }
1.126 +
1.127 + GrClipStackFrame* back = (GrClipStackFrame*) fStack.back();
1.128 +
1.129 + back->acquireMask(fContext, clipGenID, desc, bound);
1.130 + }
1.131 +
1.132 + int getLastMaskWidth() const {
1.133 +
1.134 + if (fStack.empty()) {
1.135 + SkASSERT(false);
1.136 + return -1;
1.137 + }
1.138 +
1.139 + GrClipStackFrame* back = (GrClipStackFrame*) fStack.back();
1.140 +
1.141 + if (NULL == back->fLastMask.texture()) {
1.142 + return -1;
1.143 + }
1.144 +
1.145 + return back->fLastMask.texture()->width();
1.146 + }
1.147 +
1.148 + int getLastMaskHeight() const {
1.149 +
1.150 + if (fStack.empty()) {
1.151 + SkASSERT(false);
1.152 + return -1;
1.153 + }
1.154 +
1.155 + GrClipStackFrame* back = (GrClipStackFrame*) fStack.back();
1.156 +
1.157 + if (NULL == back->fLastMask.texture()) {
1.158 + return -1;
1.159 + }
1.160 +
1.161 + return back->fLastMask.texture()->height();
1.162 + }
1.163 +
1.164 + void getLastBound(SkIRect* bound) const {
1.165 +
1.166 + if (fStack.empty()) {
1.167 + SkASSERT(false);
1.168 + bound->setEmpty();
1.169 + return;
1.170 + }
1.171 +
1.172 + GrClipStackFrame* back = (GrClipStackFrame*) fStack.back();
1.173 +
1.174 + *bound = back->fLastBound;
1.175 + }
1.176 +
1.177 + void setContext(GrContext* context) {
1.178 + fContext = context;
1.179 + }
1.180 +
1.181 + GrContext* getContext() {
1.182 + return fContext;
1.183 + }
1.184 +
1.185 + void releaseResources() {
1.186 +
1.187 + SkDeque::F2BIter iter(fStack);
1.188 + for (GrClipStackFrame* frame = (GrClipStackFrame*) iter.next();
1.189 + frame != NULL;
1.190 + frame = (GrClipStackFrame*) iter.next()) {
1.191 + frame->reset();
1.192 + }
1.193 + }
1.194 +
1.195 +private:
1.196 + struct GrClipStackFrame {
1.197 +
1.198 + GrClipStackFrame() {
1.199 + this->reset();
1.200 + }
1.201 +
1.202 + void acquireMask(GrContext* context,
1.203 + int32_t clipGenID,
1.204 + const GrTextureDesc& desc,
1.205 + const SkIRect& bound) {
1.206 +
1.207 + fLastClipGenID = clipGenID;
1.208 +
1.209 + fLastMask.set(context, desc);
1.210 +
1.211 + fLastBound = bound;
1.212 + }
1.213 +
1.214 + void reset () {
1.215 + fLastClipGenID = SkClipStack::kInvalidGenID;
1.216 +
1.217 + GrTextureDesc desc;
1.218 +
1.219 + fLastMask.set(NULL, desc);
1.220 + fLastBound.setEmpty();
1.221 + }
1.222 +
1.223 + int32_t fLastClipGenID;
1.224 + // The mask's width & height values are used by GrClipMaskManager to correctly scale the
1.225 + // texture coords for the geometry drawn with this mask.
1.226 + GrAutoScratchTexture fLastMask;
1.227 + // fLastBound stores the bounding box of the clip mask in clip-stack space. This rect is
1.228 + // used by GrClipMaskManager to position a rect and compute texture coords for the mask.
1.229 + SkIRect fLastBound;
1.230 + };
1.231 +
1.232 + GrContext* fContext;
1.233 + SkDeque fStack;
1.234 +
1.235 + typedef SkNoncopyable INHERITED;
1.236 +};
1.237 +
1.238 +#endif // GrClipMaskCache_DEFINED
