michael@0: 
michael@0: /*
michael@0:  * Copyright 2012 Google Inc.
michael@0:  *
michael@0:  * Use of this source code is governed by a BSD-style license that can be
michael@0:  * found in the LICENSE file.
michael@0:  */
michael@0: 
michael@0: #include "SkClipStack.h"
michael@0: #include "SkTLList.h"
michael@0: 
michael@0: namespace GrReducedClip {
michael@0: 
michael@0: typedef SkTLList<SkClipStack::Element> ElementList;
michael@0: 
michael@0: enum InitialState {
michael@0:     kAllIn_InitialState,
michael@0:     kAllOut_InitialState,
michael@0: };
michael@0: 
michael@0: /**
michael@0:  * This function takes a clip stack and a query rectangle and it produces a reduced set of
michael@0:  * SkClipStack::Elements that are equivalent to applying the full stack to the rectangle. The clip
michael@0:  * stack generation id that represents the list of elements is returned in resultGenID. The
michael@0:  * initial state of the query rectangle before the first clip element is applied is returned via
michael@0:  * initialState. Optionally, the caller can request a tighter bounds on the clip be returned via
michael@0:  * tighterBounds. If not NULL, tighterBounds will always be contained by queryBounds after return.
michael@0:  * If tighterBounds is specified then it is assumed that the caller will implicitly clip against it.
michael@0:  * If the caller specifies non-NULL for requiresAA then it will indicate whether anti-aliasing is
michael@0:  * required to process any of the elements in the result.
michael@0:  *
michael@0:  * This may become a member function of SkClipStack when its interface is determined to be stable.
michael@0:  * Marked SK_API so that SkLua can call this in a shared library build.
michael@0:  */
michael@0: SK_API void ReduceClipStack(const SkClipStack& stack,
michael@0:                             const SkIRect& queryBounds,
michael@0:                             ElementList* result,
michael@0:                             int32_t* resultGenID,
michael@0:                             InitialState* initialState,
michael@0:                             SkIRect* tighterBounds = NULL,
michael@0:                             bool* requiresAA = NULL);
michael@0: 
michael@0: } // namespace GrReducedClip