Create an optimized draw state but not hooked in yet to gpu pipeline

src/gpu/GrDrawState.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrDrawState.h"
+
+#include "GrDrawTargetCaps.h"
+#include "GrOptDrawState.h"
 #include "GrPaint.h"
-#include "GrDrawTargetCaps.h"
 
 //////////////////////////////////////////////////////////////////////////////s
 
+GrOptDrawState* GrDrawState::createOptState() const {
+    if (NULL == fCachedOptState) {
+        fCachedOptState = SkNEW_ARGS(GrOptDrawState, (*this));
+    } else {
+        SkASSERT(GrOptDrawState(*this) == *fCachedOptState);
+    }
+    fCachedOptState->ref();
+    return fCachedOptState;
+}
+
+//////////////////////////////////////////////////////////////////////////////s
+
 GrDrawState::CombinedState GrDrawState::CombineIfPossible(
     const GrDrawState& a, const GrDrawState& b, const GrDrawTargetCaps& caps) {
 
     if (!a.isEqual(b)) {
         return kIncompatible_CombinedState;
     }
 
     // If the general draw states are equal (from check above) we know hasColorVertexAttribute()
     // is equivalent for both a and b
     if (a.hasColorVertexAttribute()) {
@@ skipping 19 matching lines @@
                 }
             }
             return aIsOpaque ? kB_CombinedState : kA_CombinedState;
         }
     }
     return kAOrB_CombinedState;
 }
 
 //////////////////////////////////////////////////////////////////////////////s
 
-GrDrawState::GrDrawState(const GrDrawState& state, const SkMatrix& preConcatMatrix) {
+GrDrawState::GrDrawState(const GrDrawState& state, const SkMatrix& preConcatMatrix)
+    : fCachedOptState(NULL) {
     SkDEBUGCODE(fBlockEffectRemovalCnt = 0;)
     *this = state;
     if (!preConcatMatrix.isIdentity()) {
         for (int i = 0; i < this->numColorStages(); ++i) {
             fColorStages[i].localCoordChange(preConcatMatrix);
         }
         for (int i = 0; i < this->numCoverageStages(); ++i) {
             fCoverageStages[i].localCoordChange(preConcatMatrix);
         }
-        this->invalidateBlendOptFlags();
+        this->invalidateOptState();
     }
 }
 
 GrDrawState& GrDrawState::operator=(const GrDrawState& that) {
     SkASSERT(0 == fBlockEffectRemovalCnt || 0 == this->numTotalStages());
     this->setRenderTarget(that.fRenderTarget.get());
     fColor = that.fColor;
     fViewMatrix = that.fViewMatrix;
     fSrcBlend = that.fSrcBlend;
     fDstBlend = that.fDstBlend;
     fBlendConstant = that.fBlendConstant;
     fFlagBits = that.fFlagBits;
     fVACount = that.fVACount;
     fVAPtr = that.fVAPtr;
     fVertexSize = that.fVertexSize;
     fStencilSettings = that.fStencilSettings;
     fCoverage = that.fCoverage;
     fDrawFace = that.fDrawFace;
     fColorStages = that.fColorStages;
     fCoverageStages = that.fCoverageStages;
     fOptSrcBlend = that.fOptSrcBlend;
     fOptDstBlend = that.fOptDstBlend;
     fBlendOptFlags = that.fBlendOptFlags;
 
     fHints = that.fHints;
 
+    SkRefCnt_SafeAssign(fCachedOptState, that.fCachedOptState);
+
     memcpy(fFixedFunctionVertexAttribIndices,
             that.fFixedFunctionVertexAttribIndices,
             sizeof(fFixedFunctionVertexAttribIndices));
     return *this;
 }
 
 void GrDrawState::onReset(const SkMatrix* initialViewMatrix) {
     SkASSERT(0 == fBlockEffectRemovalCnt || 0 == this->numTotalStages());
     fColorStages.reset();
     fCoverageStages.reset();
@@ skipping 11 matching lines @@
     fSrcBlend = kOne_GrBlendCoeff;
     fDstBlend = kZero_GrBlendCoeff;
     fBlendConstant = 0x0;
     fFlagBits = 0x0;
     fStencilSettings.setDisabled();
     fCoverage = 0xff;
     fDrawFace = kBoth_DrawFace;
 
     fHints = 0;
 
-    this->invalidateBlendOptFlags();
+    this->invalidateOptState();
 }
 
 bool GrDrawState::setIdentityViewMatrix()  {
     if (this->numTotalStages()) {
         SkMatrix invVM;
         if (!fViewMatrix.invert(&invVM)) {
             // sad trombone sound
             return false;
         }
         for (int s = 0; s < this->numColorStages(); ++s) {
             fColorStages[s].localCoordChange(invVM);
         }
         for (int s = 0; s < this->numCoverageStages(); ++s) {
             fCoverageStages[s].localCoordChange(invVM);
         }
     }
     fViewMatrix.reset();

[bsalomon, 2014/08/28 13:49:27]

Does this not invalidate the opt state? This is a case where I think we *could*
just copy the new matrix into the opt state (if it exists) since we know the
matrix isn't used in any optimization.

[egdaniel, 2014/08/28 14:39:38]

Yeah it will invalidate the opt. In regards to copying in, how does the
localcoorcchange effect the stages? Even if the localCoordChange doesn't
directly effect optimizations, we still need to copy in the new stages. However,
at this point the optimized state may have already removed stages, moved
coverage to color, etc., that it could be not much more expensive to just
recompute the whole optState.  

[bsalomon, 2014/08/28 15:05:02]

I think a future evolution could remove GrEffectStage from GrOptDrawState and
instead have arrays of coord change matrices for color/coverage effects. Then if
the GrDS is the sole owner of the GrODS it can set a flag that GrODS's matrices
are dirty and copy the vm plus coord change matrices to GrODS next time the
createOptDrawState function is called.

     return true;
 }
 
 void GrDrawState::setFromPaint(const GrPaint& paint, const SkMatrix& vm, GrRenderTarget* rt) {
     SkASSERT(0 == fBlockEffectRemovalCnt || 0 == this->numTotalStages());
 
     fColorStages.reset();
     fCoverageStages.reset();
 
     for (int i = 0; i < paint.numColorStages(); ++i) {
@@ skipping 17 matching lines @@
 
     // Enable the clip bit
     this->enableState(GrDrawState::kClip_StateBit);
 
     this->setColor(paint.getColor());
     this->setState(GrDrawState::kDither_StateBit, paint.isDither());
     this->setState(GrDrawState::kHWAntialias_StateBit, paint.isAntiAlias());
 
     this->setBlendFunc(paint.getSrcBlendCoeff(), paint.getDstBlendCoeff());
     this->setCoverage(paint.getCoverage());
-    this->invalidateBlendOptFlags();
+    this->invalidateOptState();
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 
 static size_t vertex_size(const GrVertexAttrib* attribs, int count) {
     // this works as long as we're 4 byte-aligned
 #ifdef SK_DEBUG
     uint32_t overlapCheck = 0;
 #endif
     SkASSERT(count <= GrRODrawState::kMaxVertexAttribCnt);
@@ skipping 37 matching lines @@
             fFixedFunctionVertexAttribIndices[attribs[i].fBinding] = i;
         }
 #ifdef SK_DEBUG
         size_t dwordCount = GrVertexAttribTypeSize(attribs[i].fType) >> 2;
         uint32_t mask = (1 << dwordCount)-1;
         size_t offsetShift = attribs[i].fOffset >> 2;
         SkASSERT(!(overlapCheck & (mask << offsetShift)));
         overlapCheck |= (mask << offsetShift);
 #endif
     }
-    this->invalidateBlendOptFlags();
+    this->invalidateOptState();
     // Positions must be specified.
     SkASSERT(-1 != fFixedFunctionVertexAttribIndices[kPosition_GrVertexAttribBinding]);
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 
 void GrDrawState::setDefaultVertexAttribs() {
     static const GrVertexAttrib kPositionAttrib =
         {kVec2f_GrVertexAttribType, 0, kPosition_GrVertexAttribBinding};
 
     fVAPtr = &kPositionAttrib;
     fVACount = 1;
     fVertexSize = GrVertexAttribTypeSize(kVec2f_GrVertexAttribType);
 
     // set all the fixed function indices to -1 except position.
     memset(fFixedFunctionVertexAttribIndices,
            0xff,
            sizeof(fFixedFunctionVertexAttribIndices));
     fFixedFunctionVertexAttribIndices[kPosition_GrVertexAttribBinding] = 0;
-    this->invalidateBlendOptFlags();
+    this->invalidateOptState();
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 
 bool GrDrawState::couldApplyCoverage(const GrDrawTargetCaps& caps) const {
     if (caps.dualSourceBlendingSupport()) {
         return true;
     }
     // we can correctly apply coverage if a) we have dual source blending
     // or b) one of our blend optimizations applies
     // or c) the src, dst blend coeffs are 1,0 and we will read Dst Color
     GrBlendCoeff srcCoeff;
     GrBlendCoeff dstCoeff;
     GrRODrawState::BlendOptFlags flag = this->getBlendOpts(true, &srcCoeff, &dstCoeff);
     return GrRODrawState::kNone_BlendOpt != flag ||
            (this->willEffectReadDstColor() &&
             kOne_GrBlendCoeff == srcCoeff && kZero_GrBlendCoeff == dstCoeff);
 }
 
 //////////////////////////////////////////////////////////////////////////////
 
-GrDrawState::AutoVertexAttribRestore::AutoVertexAttribRestore(
-    GrDrawState* drawState) {
+GrDrawState::AutoVertexAttribRestore::AutoVertexAttribRestore(GrDrawState* drawState) {
     SkASSERT(NULL != drawState);
     fDrawState = drawState;
     fVAPtr = drawState->fVAPtr;
     fVACount = drawState->fVACount;
     fDrawState->setDefaultVertexAttribs();
 }
 
 //////////////////////////////////////////////////////////////////////////////s
 
 void GrDrawState::AutoRestoreEffects::set(GrDrawState* ds) {
     if (NULL != fDrawState) {
         int m = fDrawState->numColorStages() - fColorEffectCnt;
         SkASSERT(m >= 0);
         fDrawState->fColorStages.pop_back_n(m);
 
         int n = fDrawState->numCoverageStages() - fCoverageEffectCnt;
         SkASSERT(n >= 0);
         fDrawState->fCoverageStages.pop_back_n(n);
         if (m + n > 0) {
-            fDrawState->invalidateBlendOptFlags();
+            fDrawState->invalidateOptState();
         }
         SkDEBUGCODE(--fDrawState->fBlockEffectRemovalCnt;)
     }
     fDrawState = ds;
     if (NULL != ds) {
         fColorEffectCnt = ds->numColorStages();
         fCoverageEffectCnt = ds->numCoverageStages();
         SkDEBUGCODE(++ds->fBlockEffectRemovalCnt;)
     }
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 
-GrRODrawState::BlendOptFlags GrDrawState::getBlendOpts(bool forceCoverage,
-                                                       GrBlendCoeff* srcCoeff,
-                                                       GrBlendCoeff* dstCoeff) const {
-    GrBlendCoeff bogusSrcCoeff, bogusDstCoeff;
-    if (NULL == srcCoeff) {
-        srcCoeff = &bogusSrcCoeff;
-    }
-    if (NULL == dstCoeff) {
-        dstCoeff = &bogusDstCoeff;
-    }
-
-    if (forceCoverage) {
-        return this->calcBlendOpts(true, srcCoeff, dstCoeff);
-    }
-
-    if (0 == (fBlendOptFlags & kInvalid_BlendOptFlag)) {
-        *srcCoeff = fOptSrcBlend;
-        *dstCoeff = fOptDstBlend;
-        return fBlendOptFlags;
-    }
-
-    fBlendOptFlags = this->calcBlendOpts(forceCoverage, srcCoeff, dstCoeff);
-    fOptSrcBlend = *srcCoeff;
-    fOptDstBlend = *dstCoeff;
-
-    return fBlendOptFlags;
-}
-
-GrRODrawState::BlendOptFlags GrDrawState::calcBlendOpts(bool forceCoverage,
-                                                          GrBlendCoeff* srcCoeff,
-                                                          GrBlendCoeff* dstCoeff) const {
-    *srcCoeff = this->getSrcBlendCoeff();
-    *dstCoeff = this->getDstBlendCoeff();
-
-    if (this->isColorWriteDisabled()) {
-        *srcCoeff = kZero_GrBlendCoeff;
-        *dstCoeff = kOne_GrBlendCoeff;
-    }
-
-    bool srcAIsOne = this->srcAlphaWillBeOne();
-    bool dstCoeffIsOne = kOne_GrBlendCoeff == *dstCoeff ||
-                         (kSA_GrBlendCoeff == *dstCoeff && srcAIsOne);
-    bool dstCoeffIsZero = kZero_GrBlendCoeff == *dstCoeff ||
-                         (kISA_GrBlendCoeff == *dstCoeff && srcAIsOne);
-
-    // When coeffs are (0,1) there is no reason to draw at all, unless
-    // stenciling is enabled. Having color writes disabled is effectively
-    // (0,1).
-    if ((kZero_GrBlendCoeff == *srcCoeff && dstCoeffIsOne)) {
-        if (this->getStencil().doesWrite()) {
-            return kEmitCoverage_BlendOptFlag;
-        } else {
-            return kSkipDraw_BlendOptFlag;
-        }
-    }
-
-    bool hasCoverage = forceCoverage || !this->hasSolidCoverage();
-
-    // if we don't have coverage we can check whether the dst
-    // has to read at all. If not, we'll disable blending.
-    if (!hasCoverage) {
-        if (dstCoeffIsZero) {
-            if (kOne_GrBlendCoeff == *srcCoeff) {
-                // if there is no coverage and coeffs are (1,0) then we
-                // won't need to read the dst at all, it gets replaced by src
-                *dstCoeff = kZero_GrBlendCoeff;
-                return kNone_BlendOpt;
-            } else if (kZero_GrBlendCoeff == *srcCoeff) {
-                // if the op is "clear" then we don't need to emit a color
-                // or blend, just write transparent black into the dst.
-                *srcCoeff = kOne_GrBlendCoeff;
-                *dstCoeff = kZero_GrBlendCoeff;
-                return kEmitTransBlack_BlendOptFlag;
-            }
-        }
-    } else if (this->isCoverageDrawing()) {
-        // we have coverage but we aren't distinguishing it from alpha by request.
-        return kCoverageAsAlpha_BlendOptFlag;
-    } else {
-        // check whether coverage can be safely rolled into alpha
-        // of if we can skip color computation and just emit coverage
-        if (this->canTweakAlphaForCoverage()) {
-            return kCoverageAsAlpha_BlendOptFlag;
-        }
-        if (dstCoeffIsZero) {
-            if (kZero_GrBlendCoeff == *srcCoeff) {
-                // the source color is not included in the blend
-                // the dst coeff is effectively zero so blend works out to:
-                // (c)(0)D + (1-c)D = (1-c)D.
-                *dstCoeff = kISA_GrBlendCoeff;
-                return  kEmitCoverage_BlendOptFlag;
-            } else if (srcAIsOne) {
-                // the dst coeff is effectively zero so blend works out to:
-                // cS + (c)(0)D + (1-c)D = cS + (1-c)D.
-                // If Sa is 1 then we can replace Sa with c
-                // and set dst coeff to 1-Sa.
-                *dstCoeff = kISA_GrBlendCoeff;
-                return  kCoverageAsAlpha_BlendOptFlag;
-            }
-        } else if (dstCoeffIsOne) {
-            // the dst coeff is effectively one so blend works out to:
-            // cS + (c)(1)D + (1-c)D = cS + D.
-            *dstCoeff = kOne_GrBlendCoeff;
-            return  kCoverageAsAlpha_BlendOptFlag;
-        }
-    }
-
-    return kNone_BlendOpt;
-}
-
-////////////////////////////////////////////////////////////////////////////////
-
 void GrDrawState::AutoViewMatrixRestore::restore() {
     if (NULL != fDrawState) {
         SkDEBUGCODE(--fDrawState->fBlockEffectRemovalCnt;)
         fDrawState->fViewMatrix = fViewMatrix;
         SkASSERT(fDrawState->numColorStages() >= fNumColorStages);
         int numCoverageStages = fSavedCoordChanges.count() - fNumColorStages;
         SkASSERT(fDrawState->numCoverageStages() >= numCoverageStages);
 
         int i = 0;
         for (int s = 0; s < fNumColorStages; ++s, ++i) {
             fDrawState->fColorStages[s].restoreCoordChange(fSavedCoordChanges[i]);
         }
         for (int s = 0; s < numCoverageStages; ++s, ++i) {
             fDrawState->fCoverageStages[s].restoreCoordChange(fSavedCoordChanges[i]);
         }
+        fDrawState->invalidateOptState();

[bsalomon, 2014/08/28 13:49:27]

Again, could be more optimal here... There are probably lots of places like
this.

[egdaniel, 2014/08/28 14:39:38]

Again feel like this one doesn't gain much from simply copying. But there are
some other places where we may want to. I think for this cl I'd rather be over
zealous in invalidating, then go back over in a different cl and "optimize" away
these invalidations where possible

[bsalomon, 2014/08/28 15:05:02]

See comment above, but definitely don't want to do this in this CL. Just
thinking about future iterations of GrODS. It is starting to feel like the
common base class will become a burden over time, but should keep for now.

         fDrawState = NULL;
     }
 }
 
 void GrDrawState::AutoViewMatrixRestore::set(GrDrawState* drawState,
                                              const SkMatrix& preconcatMatrix) {
     this->restore();
 
     SkASSERT(NULL == fDrawState);
     if (NULL == drawState || preconcatMatrix.isIdentity()) {
         return;
     }
     fDrawState = drawState;
 
     fViewMatrix = drawState->getViewMatrix();
     drawState->fViewMatrix.preConcat(preconcatMatrix);
 
     this->doEffectCoordChanges(preconcatMatrix);
     SkDEBUGCODE(++fDrawState->fBlockEffectRemovalCnt;)
+    drawState->invalidateOptState();
 }
 
 bool GrDrawState::AutoViewMatrixRestore::setIdentity(GrDrawState* drawState) {
     this->restore();
 
     if (NULL == drawState) {
         return false;
     }
 
     if (drawState->getViewMatrix().isIdentity()) {
         return true;
     }
 
+    drawState->invalidateOptState();
     fViewMatrix = drawState->getViewMatrix();
     if (0 == drawState->numTotalStages()) {
         drawState->fViewMatrix.reset();
         fDrawState = drawState;
         fNumColorStages = 0;
         fSavedCoordChanges.reset(0);
         SkDEBUGCODE(++fDrawState->fBlockEffectRemovalCnt;)
         return true;
     } else {
         SkMatrix inv;
@@ skipping 18 matching lines @@
         fDrawState->fColorStages[s].localCoordChange(coordChangeMatrix);
     }
 
     int numCoverageStages = fDrawState->numCoverageStages();
     for (int s = 0; s < numCoverageStages; ++s, ++i) {
         fDrawState->getCoverageStage(s).saveCoordChange(&fSavedCoordChanges[i]);
         fDrawState->fCoverageStages[s].localCoordChange(coordChangeMatrix);
     }
 }
 
-bool GrDrawState::srcAlphaWillBeOne() const {
-    uint32_t validComponentFlags;
-    GrColor color;
-    // Check if per-vertex or constant color may have partial alpha
-    if (this->hasColorVertexAttribute()) {
-        if (fHints & kVertexColorsAreOpaque_Hint) {
-            validComponentFlags = kA_GrColorComponentFlag;
-            color = 0xFF << GrColor_SHIFT_A;
-        } else {
-            validComponentFlags = 0;
-            color = 0; // not strictly necessary but we get false alarms from tools about uninit.
-        }
-    } else {
-        validComponentFlags = kRGBA_GrColorComponentFlags;
-        color = this->getColor();
-    }
-
-    // Run through the color stages
-    for (int s = 0; s < this->numColorStages(); ++s) {
-        const GrEffect* effect = this->getColorStage(s).getEffect();
-        effect->getConstantColorComponents(&color, &validComponentFlags);
-    }
-
-    // Check whether coverage is treated as color. If so we run through the coverage computation.
-    if (this->isCoverageDrawing()) {
-        // The shader generated for coverage drawing runs the full coverage computation and then
-        // makes the shader output be the multiplication of color and coverage. We mirror that here.
-        GrColor coverage;
-        uint32_t coverageComponentFlags;
-        if (this->hasCoverageVertexAttribute()) {
-            coverageComponentFlags = 0;
-            coverage = 0; // suppresses any warnings.
-        } else {
-            coverageComponentFlags = kRGBA_GrColorComponentFlags;
-            coverage = this->getCoverageColor();
-        }
-
-        // Run through the coverage stages
-        for (int s = 0; s < this->numCoverageStages(); ++s) {
-            const GrEffect* effect = this->getCoverageStage(s).getEffect();
-            effect->getConstantColorComponents(&coverage, &coverageComponentFlags);
-        }
-
-        // Since the shader will multiply coverage and color, the only way the final A==1 is if
-        // coverage and color both have A==1.
-        return (kA_GrColorComponentFlag & validComponentFlags & coverageComponentFlags) &&
-                0xFF == GrColorUnpackA(color) && 0xFF == GrColorUnpackA(coverage);
-
-    }
-
-    return (kA_GrColorComponentFlag & validComponentFlags) && 0xFF == GrColorUnpackA(color);
-}
-
-////////////////////////////////////////////////////////////////////////////////
-
-bool GrDrawState::canIgnoreColorAttribute() const {
-    if (fBlendOptFlags & kInvalid_BlendOptFlag) {
-        this->getBlendOpts();
-    }
-    return SkToBool(fBlendOptFlags & (GrRODrawState::kEmitTransBlack_BlendOptFlag |
-                                      GrRODrawState::kEmitCoverage_BlendOptFlag));
-}
-