blob: 6ba1cd76e30a7a3ad8bc30a6b573de42b27b6bb2 [file] [log] [blame]
/*
* Copyright 2019 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef SkSharingProc_DEFINED
#define SkSharingProc_DEFINED
#include <unordered_map>
#include <vector>
#include "include/core/SkData.h"
#include "include/core/SkImage.h"
#include "include/core/SkSerialProcs.h"
#include "src/core/SkTHash.h"
/**
* This serial proc serializes each image it encounters only once, using their uniqueId as the
* property for sameness.
*
* It's most basic usage involves setting your imageProc to SkSharingSerialContext::serializeImage
* and creating an SkSharingSerialContext in an appropriate scope to outlive all the images that
* will be encountered before serialization.
*
* Optionally, collectNonTextureImagesFromPicture can be called with an SkSharingContext and an
* SkPicture that may reference not-yet-released texture backed images. It will make non-texture
* copies if necessary and store them in the context. If present, they will be used in the
* final serialization.
*
* This is intended to be used on Android with MultiPictureDocument's onEndPage parameter, in a
* lambda that captures the context, because MPD cannot make assumptions about the type of proc it
* receives and clients (Chrome) build MPD without this source file.
*/
struct SkSharingSerialContext {
// --- Data and and function for optional texture collection pass --- //
// A map from uniqueID of images referenced by commands to non-texture images
// collected at the end of each frame.
skia_private::THashMap<uint32_t, sk_sp<SkImage>> fNonTexMap;
// Collects any non-texture images referenced by the picture and stores non-texture copies
// in the fNonTexMap of the provided SkSharingContext
static void collectNonTextureImagesFromPicture(
const SkPicture* pic, SkSharingSerialContext* sharingCtx);
// --- Data and serialization function for regular use --- //
// A map from the ids from SkImage::uniqueID() to ids used within the file
// The keys are ids of original images, not of non-texture copies
skia_private::THashMap<uint32_t, int> fImageMap;
// A serial proc that shares images between subpictures
// To use this, create an instance of SkSerialProcs and populate it this way.
// The client must retain ownership of the context.
// auto ctx = std::make_unique<SkSharingSerialContext>()
// SkSerialProcs procs;
// procs.fImageProc = SkSharingSerialContext::serializeImage;
// procs.fImageCtx = ctx.get();
static sk_sp<SkData> serializeImage(SkImage* img, void* ctx);
};
struct SkSharingDeserialContext {
// a list of unique images in the order they were encountered in the file
// Subsequent occurrences of an image refer to it by it's index in this list.
std::vector<sk_sp<SkImage>> fImages;
// A deserial proc that can interpret id's in place of images as references to previous images.
// Can also deserialize a SKP where all images are inlined (it's backwards compatible)
static sk_sp<SkImage> deserializeImage(const void* data, size_t length, void* ctx);
};
#endif