Exemplo n.º 1
0
void GrBitmapTextContext::flushGlyphs() {
    if (NULL == fDrawTarget) {
        return;
    }

    GrDrawState* drawState = fDrawTarget->drawState();
    GrDrawState::AutoRestoreEffects are(drawState);
    drawState->setFromPaint(fPaint, SkMatrix::I(), fContext->getRenderTarget());

    if (fCurrVertex > 0) {
        // setup our sampler state for our text texture/atlas
        SkASSERT(SkIsAlign4(fCurrVertex));
        GrTextureParams params(SkShader::kRepeat_TileMode, GrTextureParams::kNone_FilterMode);

        GrTexture* currTexture = fStrike->getTexture();
        SkASSERT(currTexture);
        uint32_t textureUniqueID = currTexture->getUniqueID();
        
        if (textureUniqueID != fEffectTextureUniqueID) {
            fCachedEffect.reset(GrCustomCoordsTextureEffect::Create(currTexture, params));
            fEffectTextureUniqueID = textureUniqueID;
        }

        // This effect could be stored with one of the cache objects (atlas?)
        int coordsIdx = drawState->hasColorVertexAttribute() ? kGlyphCoordsWithColorAttributeIndex :
                                                               kGlyphCoordsNoColorAttributeIndex;
        drawState->addCoverageEffect(fCachedEffect.get(), coordsIdx);
        SkASSERT(NULL != fStrike);
        switch (fStrike->getMaskFormat()) {
            // Color bitmap text
            case kARGB_GrMaskFormat:
                SkASSERT(!drawState->hasColorVertexAttribute());
                drawState->setBlendFunc(fPaint.getSrcBlendCoeff(), fPaint.getDstBlendCoeff());
                drawState->setColor(0xffffffff);
                break;
            // LCD text
            case kA888_GrMaskFormat:
            case kA565_GrMaskFormat: {
                if (kOne_GrBlendCoeff != fPaint.getSrcBlendCoeff() ||
                    kISA_GrBlendCoeff != fPaint.getDstBlendCoeff() ||
                    fPaint.numColorStages()) {
                    GrPrintf("LCD Text will not draw correctly.\n");
                }
                SkASSERT(!drawState->hasColorVertexAttribute());
                // We don't use the GrPaint's color in this case because it's been premultiplied by
                // alpha. Instead we feed in a non-premultiplied color, and multiply its alpha by
                // the mask texture color. The end result is that we get
                //            mask*paintAlpha*paintColor + (1-mask*paintAlpha)*dstColor
                int a = SkColorGetA(fSkPaint.getColor());
                // paintAlpha
                drawState->setColor(SkColorSetARGB(a, a, a, a));
                // paintColor
                drawState->setBlendConstant(skcolor_to_grcolor_nopremultiply(fSkPaint.getColor()));
                drawState->setBlendFunc(kConstC_GrBlendCoeff, kISC_GrBlendCoeff);
                break;
            }
            // Grayscale/BW text
            case kA8_GrMaskFormat:
                // set back to normal in case we took LCD path previously.
                drawState->setBlendFunc(fPaint.getSrcBlendCoeff(), fPaint.getDstBlendCoeff());
                //drawState->setColor(fPaint.getColor());
                // We're using per-vertex color.
                SkASSERT(drawState->hasColorVertexAttribute());
                drawState->setColor(0xFFFFFFFF);
                break;
            default:
                SkFAIL("Unexepected mask format.");
        }
        int nGlyphs = fCurrVertex / 4;
        fDrawTarget->setIndexSourceToBuffer(fContext->getQuadIndexBuffer());
        fDrawTarget->drawIndexedInstances(kTriangles_GrPrimitiveType,
                                          nGlyphs,
                                          4, 6, &fVertexBounds);

        fCurrVertex = 0;
        fVertexBounds.setLargestInverted();
    }

    fDrawTarget->resetVertexSource();
    fVertices = NULL;
}