bsalomon@google.com | ded4f4b | 2012-06-28 18:48:06 +0000 | [diff] [blame^] | 1 | |
| 2 | /* |
| 3 | * Copyright 2012 Google Inc. |
| 4 | * |
| 5 | * Use of this source code is governed by a BSD-style license that can be |
| 6 | * found in the LICENSE file. |
| 7 | */ |
| 8 | |
| 9 | |
| 10 | #include "GrStencilAndCoverPathRenderer.h" |
| 11 | #include "GrContext.h" |
| 12 | #include "GrGpu.h" |
| 13 | #include "GrPath.h" |
| 14 | |
| 15 | GrPathRenderer* GrStencilAndCoverPathRenderer::Create(GrContext* context) { |
| 16 | GrAssert(NULL != context); |
| 17 | GrAssert(NULL != context->getGpu()); |
| 18 | if (context->getGpu()->getCaps().fPathStencilingSupport) { |
| 19 | return new GrStencilAndCoverPathRenderer(context->getGpu()); |
| 20 | } else { |
| 21 | return NULL; |
| 22 | } |
| 23 | } |
| 24 | |
| 25 | GrStencilAndCoverPathRenderer::GrStencilAndCoverPathRenderer(GrGpu* gpu) { |
| 26 | GrAssert(gpu->getCaps().fPathStencilingSupport); |
| 27 | fGpu = gpu; |
| 28 | gpu->ref(); |
| 29 | } |
| 30 | |
| 31 | GrStencilAndCoverPathRenderer::~GrStencilAndCoverPathRenderer() { |
| 32 | fGpu->unref(); |
| 33 | } |
| 34 | |
| 35 | bool GrStencilAndCoverPathRenderer::canDrawPath(const SkPath& path, |
| 36 | GrPathFill fill, |
| 37 | const GrDrawTarget* target, |
| 38 | bool antiAlias) const { |
| 39 | return kHairLine_GrPathFill != fill && |
| 40 | !antiAlias && // doesn't do per-path AA, relies on the target having MSAA |
| 41 | target->getDrawState().getStencil().isDisabled(); |
| 42 | } |
| 43 | |
| 44 | bool GrStencilAndCoverPathRenderer::requiresStencilPass(const SkPath& path, |
| 45 | GrPathFill fill, |
| 46 | const GrDrawTarget* target) const { |
| 47 | return true; |
| 48 | } |
| 49 | |
| 50 | void GrStencilAndCoverPathRenderer::drawPathToStencil(const SkPath& path, |
| 51 | GrPathFill fill, |
| 52 | GrDrawTarget* target) { |
| 53 | GrAssert(kEvenOdd_GrPathFill == fill || kWinding_GrPathFill == fill); |
| 54 | SkAutoTUnref<GrPath> p(fGpu->createPath(path)); |
| 55 | target->stencilPath(p, fill); |
| 56 | } |
| 57 | |
| 58 | bool GrStencilAndCoverPathRenderer::onDrawPath(const SkPath& path, |
| 59 | GrPathFill fill, |
| 60 | const GrVec* translate, |
| 61 | GrDrawTarget* target, |
| 62 | GrDrawState::StageMask stageMask, |
| 63 | bool antiAlias){ |
| 64 | GrAssert(!antiAlias); |
| 65 | GrAssert(kHairLine_GrPathFill != fill); |
| 66 | |
| 67 | GrDrawState* drawState = target->drawState(); |
| 68 | GrAssert(drawState->getStencil().isDisabled()); |
| 69 | |
| 70 | SkAutoTUnref<GrPath> p(fGpu->createPath(path)); |
| 71 | GrDrawState::AutoViewMatrixRestore avmr; |
| 72 | if (translate) { |
| 73 | avmr.set(drawState); |
| 74 | drawState->viewMatrix()->postTranslate(translate->fX, translate->fY); |
| 75 | } |
| 76 | GrPathFill nonInvertedFill = GrNonInvertedFill(fill); |
| 77 | target->stencilPath(p, nonInvertedFill); |
| 78 | |
| 79 | // TODO: Use built in cover operation rather than a rect draw. This will require making our |
| 80 | // fragment shaders be able to eat varyings generated by a matrix. |
| 81 | |
| 82 | // fill the path, zero out the stencil |
| 83 | GrRect bounds = p->getBounds(); |
| 84 | GrScalar bloat = drawState->getViewMatrix().getMaxStretch() * GR_ScalarHalf; |
| 85 | if (nonInvertedFill == fill) { |
| 86 | GR_STATIC_CONST_SAME_STENCIL(kStencilPass, |
| 87 | kZero_StencilOp, |
| 88 | kZero_StencilOp, |
| 89 | kNotEqual_StencilFunc, |
| 90 | 0xffff, |
| 91 | 0x0000, |
| 92 | 0xffff); |
| 93 | *drawState->stencil() = kStencilPass; |
| 94 | } else { |
| 95 | GR_STATIC_CONST_SAME_STENCIL(kInvertedStencilPass, |
| 96 | kZero_StencilOp, |
| 97 | kZero_StencilOp, |
| 98 | kEqual_StencilFunc, |
| 99 | 0xffff, |
| 100 | 0x0000, |
| 101 | 0xffff); |
| 102 | GrMatrix vmi; |
| 103 | bounds.setLTRB(0, 0, |
| 104 | GrIntToScalar(drawState->getRenderTarget()->width()), |
| 105 | GrIntToScalar(drawState->getRenderTarget()->height())); |
| 106 | // mapRect through persp matrix may not be correct |
| 107 | if (!drawState->getViewMatrix().hasPerspective() && drawState->getViewInverse(&vmi)) { |
| 108 | vmi.mapRect(&bounds); |
| 109 | // theoretically could set bloat = 0, instead leave it because of matrix inversion precision. |
| 110 | } else { |
| 111 | if (stageMask) { |
| 112 | if (!drawState->getViewInverse(&vmi)) { |
| 113 | GrPrintf("Could not invert matrix."); |
| 114 | return false; |
| 115 | } |
| 116 | drawState->preConcatSamplerMatrices(stageMask, vmi); |
| 117 | } |
| 118 | if (avmr.isSet()) { |
| 119 | avmr.set(drawState); |
| 120 | } |
| 121 | drawState->viewMatrix()->reset(); |
| 122 | bloat = 0; |
| 123 | } |
| 124 | *drawState->stencil() = kInvertedStencilPass; |
| 125 | } |
| 126 | bounds.outset(bloat, bloat); |
| 127 | target->drawSimpleRect(bounds, NULL, stageMask); |
| 128 | target->drawState()->stencil()->setDisabled(); |
| 129 | return true; |
| 130 | } |