skia2/include/core/SkVertices.h
Mike Reed 165fa634b7 check for valid vertices mode
Bug: skia:7512
Change-Id: I2ede2232f3807e7bad8562eb3bf6327ffc52a996
Reviewed-on: https://skia-review.googlesource.com/98760
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Mike Reed <reed@google.com>
2018-01-23 18:28:47 +00:00

142 lines
4.7 KiB
C++

/*
* Copyright 2017 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef SkVertices_DEFINED
#define SkVertices_DEFINED
#include "SkColor.h"
#include "SkData.h"
#include "SkPoint.h"
#include "SkRect.h"
#include "SkRefCnt.h"
/**
* An immutable set of vertex data that can be used with SkCanvas::drawVertices.
*/
class SK_API SkVertices : public SkNVRefCnt<SkVertices> {
public:
enum VertexMode {
kTriangles_VertexMode,
kTriangleStrip_VertexMode,
kTriangleFan_VertexMode,
kLast_VertexMode = kTriangleFan_VertexMode,
};
/**
* Create a vertices by copying the specified arrays. texs and colors may be nullptr,
* and indices is ignored if indexCount == 0.
*/
static sk_sp<SkVertices> MakeCopy(VertexMode mode, int vertexCount,
const SkPoint positions[],
const SkPoint texs[],
const SkColor colors[],
int indexCount,
const uint16_t indices[]);
static sk_sp<SkVertices> MakeCopy(VertexMode mode, int vertexCount,
const SkPoint positions[],
const SkPoint texs[],
const SkColor colors[]) {
return MakeCopy(mode, vertexCount, positions, texs, colors, 0, nullptr);
}
struct Sizes;
enum BuilderFlags {
kHasTexCoords_BuilderFlag = 1 << 0,
kHasColors_BuilderFlag = 1 << 1,
};
class Builder {
public:
Builder(VertexMode mode, int vertexCount, int indexCount, uint32_t flags);
bool isValid() const { return fVertices != nullptr; }
// if the builder is invalid, these will return 0
int vertexCount() const;
int indexCount() const;
SkPoint* positions();
SkPoint* texCoords(); // returns null if there are no texCoords
SkColor* colors(); // returns null if there are no colors
uint16_t* indices(); // returns null if there are no indices
// Detach the built vertices object. After the first call, this will always return null.
sk_sp<SkVertices> detach();
private:
Builder(VertexMode mode, int vertexCount, int indexCount, const Sizes&);
void init(VertexMode mode, int vertexCount, int indexCount, const Sizes&);
// holds a partially complete object. only completed in detach()
sk_sp<SkVertices> fVertices;
friend class SkVertices;
};
uint32_t uniqueID() const { return fUniqueID; }
VertexMode mode() const { return fMode; }
const SkRect& bounds() const { return fBounds; }
bool hasColors() const { return SkToBool(this->colors()); }
bool hasTexCoords() const { return SkToBool(this->texCoords()); }
bool hasIndices() const { return SkToBool(this->indices()); }
int vertexCount() const { return fVertexCnt; }
const SkPoint* positions() const { return fPositions; }
const SkPoint* texCoords() const { return fTexs; }
const SkColor* colors() const { return fColors; }
int indexCount() const { return fIndexCnt; }
const uint16_t* indices() const { return fIndices; }
// returns approximate byte size of the vertices object
size_t approximateSize() const;
/**
* Recreate a vertices from a buffer previously created by calling encode().
* Returns null if the data is corrupt or the length is incorrect for the contents.
*/
static sk_sp<SkVertices> Decode(const void* buffer, size_t length);
/**
* Pack the vertices object into a byte buffer. This can be used to recreate the vertices
* by calling Decode() with the buffer.
*/
sk_sp<SkData> encode() const;
private:
SkVertices() {}
// these are needed since we've manually sized our allocation (see Builder::init)
friend class SkNVRefCnt<SkVertices>;
void operator delete(void* p) { ::operator delete(p); }
static sk_sp<SkVertices> Alloc(int vCount, int iCount, uint32_t builderFlags,
size_t* arraySize);
// we store this first, to pair with the refcnt in our base-class, so we don't have an
// unnecessary pad between it and the (possibly 8-byte aligned) ptrs.
uint32_t fUniqueID;
// these point inside our allocation, so none of these can be "freed"
SkPoint* fPositions;
SkPoint* fTexs;
SkColor* fColors;
uint16_t* fIndices;
SkRect fBounds; // computed to be the union of the fPositions[]
int fVertexCnt;
int fIndexCnt;
VertexMode fMode;
// below here is where the actual array data is stored.
};
#endif