Ejemplo n.º 1
0
void GrDistanceFieldTextContext::flush() {
    if (NULL == fDrawTarget) {
        return;
    }

    if (fCurrVertex > 0) {
        GrDrawState drawState;
        drawState.setFromPaint(fPaint, fContext->getMatrix(), fContext->getRenderTarget());
        bool useColorVerts = !fUseLCDText;
        set_vertex_attributes(&drawState, useColorVerts);

        // setup our sampler state for our text texture/atlas
        SkASSERT(SkIsAlign4(fCurrVertex));

        // get our current color
        SkColor filteredColor;
        SkColorFilter* colorFilter = fSkPaint.getColorFilter();
        if (colorFilter) {
            filteredColor = colorFilter->filterColor(fSkPaint.getColor());
        } else {
            filteredColor = fSkPaint.getColor();
        }
        this->setupCoverageEffect(filteredColor);

        // Effects could be stored with one of the cache objects (atlas?)
        drawState.setGeometryProcessor(fCachedGeometryProcessor.get());

        // Set draw state
        if (fUseLCDText) {
            GrColor colorNoPreMul = skcolor_to_grcolor_nopremultiply(filteredColor);
            if (kOne_GrBlendCoeff != fPaint.getSrcBlendCoeff() ||
                kISA_GrBlendCoeff != fPaint.getDstBlendCoeff() ||
                fPaint.numColorStages()) {
                SkDebugf("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(colorNoPreMul);
            drawState.setBlendFunc(kConstC_GrBlendCoeff, kISC_GrBlendCoeff);
        } else {
            if (0xFF == GrColorUnpackA(fPaint.getColor())) {
                drawState.setHint(GrDrawState::kVertexColorsAreOpaque_Hint, true);
            }
            // set back to normal in case we took LCD path previously.
            drawState.setBlendFunc(fPaint.getSrcBlendCoeff(), fPaint.getDstBlendCoeff());
            // We're using per-vertex color.
            SkASSERT(drawState.hasColorVertexAttribute());
        }
        int nGlyphs = fCurrVertex / kVerticesPerGlyph;
        fDrawTarget->setIndexSourceToBuffer(fContext->getQuadIndexBuffer());
        fDrawTarget->drawIndexedInstances(&drawState,
                                          kTriangles_GrPrimitiveType,
                                          nGlyphs,
                                          kVerticesPerGlyph,
                                          kIndicesPerGlyph,
                                          &fVertexBounds);
        fDrawTarget->resetVertexSource();
        fVertices = NULL;
        fTotalVertexCount -= fCurrVertex;
        fCurrVertex = 0;
        SkSafeSetNull(fCurrTexture);
        fVertexBounds.setLargestInverted();
    }
}