1/*
2 * Copyright 2011 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8
9
10#ifndef GrGLIRect_DEFINED
11#define GrGLIRect_DEFINED
12
13#include "gl/GrGLInterface.h"
14#include "GrGLUtil.h"
15
16/**
17 * Helper struct for dealing with the fact that Ganesh and GL use different
18 * window coordinate systems (top-down vs bottom-up)
19 */
20struct GrGLIRect {
21    GrGLint   fLeft;
22    GrGLint   fBottom;
23    GrGLsizei fWidth;
24    GrGLsizei fHeight;
25
26    void pushToGLViewport(const GrGLInterface* gl) const {
27        GR_GL_CALL(gl, Viewport(fLeft, fBottom, fWidth, fHeight));
28    }
29
30    void pushToGLScissor(const GrGLInterface* gl) const {
31        GR_GL_CALL(gl, Scissor(fLeft, fBottom, fWidth, fHeight));
32    }
33
34    void setFromGLViewport(const GrGLInterface* gl) {
35        GR_STATIC_ASSERT(sizeof(GrGLIRect) == 4*sizeof(GrGLint));
36        GR_GL_GetIntegerv(gl, GR_GL_VIEWPORT, (GrGLint*) this);
37    }
38
39    // sometimes we have a GrIRect from the client that we
40    // want to simultaneously make relative to GL's viewport
41    // and convert from top-down to bottom-up.
42    void setRelativeTo(const GrGLIRect& glRect,
43                       int leftOffset,
44                       int topOffset,
45                       int width,
46                       int height) {
47        fLeft = glRect.fLeft + leftOffset;
48        fWidth = width;
49        fBottom = glRect.fBottom + (glRect.fHeight - topOffset - height);
50        fHeight = height;
51
52        GrAssert(fLeft >= 0);
53        GrAssert(fWidth >= 0);
54        GrAssert(fBottom >= 0);
55        GrAssert(fHeight >= 0);
56    }
57
58    bool contains(const GrGLIRect& glRect) const {
59        return fLeft <= glRect.fLeft &&
60               fBottom <= glRect.fBottom &&
61               fLeft + fWidth >=  glRect.fLeft + glRect.fWidth &&
62               fBottom + fHeight >=  glRect.fBottom + glRect.fHeight;
63    }
64
65    void invalidate() {fLeft = fWidth = fBottom = fHeight = -1;}
66
67    bool operator ==(const GrGLIRect& glRect) const {
68        return 0 == memcmp(this, &glRect, sizeof(GrGLIRect));
69    }
70
71    bool operator !=(const GrGLIRect& glRect) const {return !(*this == glRect);}
72};
73
74#endif
75