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Commit 8a5cc92a authored by Chet Haase's avatar Chet Haase
Browse files

Fix various hw-accelerated line/point bugs 

All accelerated lines are now rendered as quads. Hairlines used to
be rendered as GL_LINES, but these lines don't render the same as our
non-accelerated lines, so we're using quads for everything. Also, fixed
a bug in the way that we were offsetting quads (and not offseting points)
to ensure that our lines/points actuall start on the same pixels as
Skia's.

Change-Id: I51b923cc08a9858444c430ba07bc8aa0c83cbe6a
parent b4a56f10

libs/hwui/OpenGLRenderer.cpp

+63 −89
Original line number Diff line number Diff line
@@ -979,8 +979,8 @@ void OpenGLRenderer::setupDrawModelViewTranslate(float left, float top, float ri 
    }

}



void OpenGLRenderer::setupDrawModelViewIdentity() {

    mCaches.currentProgram->set(mOrthoMatrix, mIdentity, *mSnapshot->transform);

void OpenGLRenderer::setupDrawModelViewIdentity(bool offset) {

    mCaches.currentProgram->set(mOrthoMatrix, mIdentity, *mSnapshot->transform, offset);

}



void OpenGLRenderer::setupDrawModelView(float left, float top, float right, float bottom,
@@ -1389,13 +1389,46 @@ void OpenGLRenderer::drawPatch(SkBitmap* bitmap, const int32_t* xDivs, const int 
    }

}



void OpenGLRenderer::drawLinesAsQuads(float *points, int count, bool isAA, bool isHairline,

        float strokeWidth) {

void OpenGLRenderer::drawLines(float* points, int count, SkPaint* paint) {

    if (mSnapshot->isIgnored()) return;



    const bool isAA = paint->isAntiAlias();

    float strokeWidth = paint->getStrokeWidth() * 0.5f;

    // A stroke width of 0 has a special meaning in Skia:

    // it draws a line 1 px wide regardless of current transform

    bool isHairLine = paint->getStrokeWidth() == 0.0f;

    int alpha;

    SkXfermode::Mode mode;

    int generatedVerticesCount = 0;

    int verticesCount = count;

    if (count > 4) {

        // Polyline: account for extra vertices needed for continous tri-strip

        verticesCount += (count -4);

    }



    getAlphaAndMode(paint, &alpha, &mode);

    setupDraw();

    if (isAA) {

        setupDrawAALine();

    }

    setupDrawColor(paint->getColor(), alpha);

    setupDrawColorFilter();

    setupDrawShader();

    if (isAA) {

        setupDrawBlending(true, mode);

    } else {

        setupDrawBlending(mode);

    }

    setupDrawProgram();

    setupDrawModelViewIdentity(true);

    setupDrawColorUniforms();

    setupDrawColorFilterUniforms();

    setupDrawShaderIdentityUniforms();



    if (isHairLine) {

        // Set a real stroke width to be used in quad construction

        strokeWidth = .5;

    }

    if (isAA) {

        // Expand boundary to enable AA calculations on the quad border

        strokeWidth += .5f;
@@ -1407,25 +1440,22 @@ void OpenGLRenderer::drawLinesAsQuads(float *points, int count, bool isAA, bool 
    if (!isAA) {

        setupDrawVertices(vertices);

    } else {

        AlphaVertex* alphaCoords = aaVertices + gVertexAlphaOffset;

        void* alphaCoords = ((GLbyte*) aaVertices) + gVertexAlphaOffset;

        // innerProportion is the ratio of the inner (non-AA) port of the line to the total

        // AA stroke width (the base stroke width expanded by a half pixel on either side).

        // This value is used in the fragment shader to determine how to fill fragments.

        float innerProportion = fmax(strokeWidth - 1.0f, 0) / (strokeWidth + .5f);

        setupDrawAALine((void*) aaVertices, (void*) alphaCoords, innerProportion);

        setupDrawAALine((void*) aaVertices, alphaCoords, innerProportion);

    }



    int generatedVerticesCount = 0;

    AlphaVertex *prevAAVertex = NULL;

    Vertex *prevVertex = NULL;

    float inverseScaleX = 1.0f;

    float inverseScaleY = 1.0f;



    if (isHairline) {

    if (isHairLine) {

        // The quad that we use for AA hairlines needs to account for scaling because the line

        // should always be one pixel wide regardless of scale.

        inverseScaleX = 1.0f;

        inverseScaleY = 1.0f;

        if (!mSnapshot->transform->isPureTranslate()) {

            Matrix4 *mat = mSnapshot->transform;

            float m00 = mat->data[Matrix4::kScaleX];
@@ -1446,23 +1476,20 @@ void OpenGLRenderer::drawLinesAsQuads(float *points, int count, bool isAA, bool 
        vec2 a(points[i], points[i + 1]);

        vec2 b(points[i + 2], points[i + 3]);



        // Bias to snap to the same pixels as Skia

        a += 0.375;

        b += 0.375;



        // Find the normal to the line

        vec2 n = (b - a).copyNormalized() * strokeWidth;

        if (isHairline) {

        if (isHairLine) {

            n *= inverseScaleX;

            if (isAA) {

                float wideningFactor;

                if (fabs(n.x) >= fabs(n.y)) {

                    wideningFactor = fabs(1.0f / n.x);

                } else {

                    wideningFactor = fabs(1.0f / n.y);

                }

            n.x *= inverseScaleX;

            n.y *= inverseScaleY;

                n *= wideningFactor;

            }

        }

        float x = n.x;

        n.x = -n.y;

        n.y = x;
@@ -1525,69 +1552,6 @@ void OpenGLRenderer::drawLinesAsQuads(float *points, int count, bool isAA, bool 
    }

}



void OpenGLRenderer::drawLines(float* points, int count, SkPaint* paint) {

    if (mSnapshot->isIgnored()) return;



    const bool isAA = paint->isAntiAlias();

    const float strokeWidth = paint->getStrokeWidth() * 0.5f;

    // A stroke width of 0 has a special meaning in Skia:

    // it draws a line 1 px wide regardless of current transform

    bool isHairLine = paint->getStrokeWidth() == 0.0f;



    int alpha;

    SkXfermode::Mode mode;

    getAlphaAndMode(paint, &alpha, &mode);

    int generatedVerticesCount = 0;



    setupDraw();

    if (isAA) {

        setupDrawAALine();

    }

    setupDrawColor(paint->getColor(), alpha);

    setupDrawColorFilter();

    setupDrawShader();

    if (isAA) {

        setupDrawBlending(true, mode);

    } else {

        setupDrawBlending(mode);

    }

    setupDrawProgram();

    setupDrawModelViewIdentity();

    setupDrawColorUniforms();

    setupDrawColorFilterUniforms();

    setupDrawShaderIdentityUniforms();



    if (!isHairLine) {

        drawLinesAsQuads(points, count, isAA, isHairLine, strokeWidth);

    } else {

        if (isAA) {

            drawLinesAsQuads(points, count, isAA, isHairLine, .5f);

        } else {

            int verticesCount = count >> 1;

            Vertex lines[verticesCount];

            Vertex* vertices = &lines[0];

            setupDrawVertices(vertices);

            for (int i = 0; i < count; i += 4) {



                const float left = fmin(points[i], points[i + 2]);

                const float right = fmax(points[i], points[i + 2]);

                const float top = fmin(points[i + 1], points[i + 3]);

                const float bottom = fmax(points[i + 1], points[i + 3]);



                Vertex::set(vertices++, points[i], points[i + 1]);

                Vertex::set(vertices++, points[i + 2], points[i + 3]);

                generatedVerticesCount += 2;

                dirtyLayer(left, top,

                        right == left ? left + 1 : right, bottom == top ? top + 1 : bottom,

                        *mSnapshot->transform);

            }



            glLineWidth(1.0f);

            glDrawArrays(GL_LINES, 0, generatedVerticesCount);

        }

    }

}



void OpenGLRenderer::drawPoints(float* points, int count, SkPaint* paint) {

    if (mSnapshot->isIgnored()) return;
@@ -1596,8 +1560,13 @@ void OpenGLRenderer::drawPoints(float* points, int count, SkPaint* paint) { 


    // A stroke width of 0 has a special meaning in Skia:

    // it draws an unscaled 1px point

    float strokeWidth = paint->getStrokeWidth();

    const bool isHairLine = paint->getStrokeWidth() == 0.0f;



    if (isHairLine) {

        // Now that we know it's hairline, we can set the effective width, to be used later

        strokeWidth = 1.0f;

    }

    const float halfWidth = strokeWidth / 2;

    int alpha;

    SkXfermode::Mode mode;

    getAlphaAndMode(paint, &alpha, &mode);
@@ -1609,13 +1578,13 @@ void OpenGLRenderer::drawPoints(float* points, int count, SkPaint* paint) { 
    TextureVertex* vertex = &pointsData[0];



    setupDraw();

    setupDrawPoint(isHairLine ? 1.0f : paint->getStrokeWidth());

    setupDrawPoint(strokeWidth);

    setupDrawColor(paint->getColor(), alpha);

    setupDrawColorFilter();

    setupDrawShader();

    setupDrawBlending(mode);

    setupDrawProgram();

    setupDrawModelViewIdentity();

    setupDrawModelViewIdentity(true);

    setupDrawColorUniforms();

    setupDrawColorFilterUniforms();

    setupDrawPointUniforms();
@@ -1625,6 +1594,11 @@ void OpenGLRenderer::drawPoints(float* points, int count, SkPaint* paint) { 
    for (int i = 0; i < count; i += 2) {

        TextureVertex::set(vertex++, points[i], points[i + 1], 0.0f, 0.0f);

        generatedVerticesCount++;

        float left = points[i] - halfWidth;

        float right = points[i] + halfWidth;

        float top = points[i + 1] - halfWidth;

        float bottom = points [i + 1] + halfWidth;

        dirtyLayer(left, top, right, bottom, *mSnapshot->transform);

    }



    glDrawArrays(GL_POINTS, 0, generatedVerticesCount);

libs/hwui/OpenGLRenderer.h

+1 −14
Original line number Diff line number Diff line
@@ -282,19 +282,6 @@ private: 


    void drawAlphaBitmap(Texture* texture, float left, float top, SkPaint* paint);



    /**

     * Draws a line as a quad. Called by drawLines() for all cases except hairline without AA.

     *

     * @param points The vertices of the lines. Every four entries specifies the x/y points

     * of a single line segment.

     * @param count The number of entries in the points array.

     * @param isAA Whether the line is anti-aliased

     * @param isHairline Whether the line has strokeWidth==0, which results in the line being

     * one pixel wide on the display regardless of scale.

     */

    void drawLinesAsQuads(float *points, int count, bool isAA, bool isHairline,

            float strokeWidth);



    /**

     * Draws a textured rectangle with the specified texture. The specified coordinates

     * are transformed by the current snapshot's transform matrix.
@@ -453,7 +440,7 @@ private: 
            bool swapSrcDst = false);

    void setupDrawProgram();

    void setupDrawDirtyRegionsDisabled();

    void setupDrawModelViewIdentity();

    void setupDrawModelViewIdentity(bool offset = false);

    void setupDrawModelView(float left, float top, float right, float bottom,

            bool ignoreTransform = false, bool ignoreModelView = false);

    void setupDrawModelViewTranslate(float left, float top, float right, float bottom,

libs/hwui/Program.cpp

+8 −1
Original line number Diff line number Diff line
@@ -124,8 +124,15 @@ GLuint Program::buildShader(const char* source, GLenum type) { 
}



void Program::set(const mat4& projectionMatrix, const mat4& modelViewMatrix,

        const mat4& transformMatrix) {

        const mat4& transformMatrix, bool offset) {

    mat4 t(projectionMatrix);

    if (offset) {

        // offset screenspace xy by an amount that compensates for typical precision issues

        // in GPU hardware that tends to paint hor/vert lines in pixels shifted up and to the left.

        // This offset value is based on an assumption that some hardware may use as little

        // as 12.4 precision, so we offset by slightly more than 1/16.

        t.translate(.375, .375, 0);

    }

    t.multiply(transformMatrix);

    t.multiply(modelViewMatrix);

libs/hwui/Program.h

+1 −1
Original line number Diff line number Diff line
@@ -81,7 +81,7 @@ public: 
     * transform matrices.

     */

    void set(const mat4& projectionMatrix, const mat4& modelViewMatrix,

             const mat4& transformMatrix);

             const mat4& transformMatrix, bool offset = false);



    /**

     * Sets the color associated with this shader.

tests/HwAccelerationTest/AndroidManifest.xml

+9 −0
Original line number Diff line number Diff line
@@ -405,6 +405,15 @@ 
            </intent-filter>

        </activity>



        <activity

                android:name="PointsActivity"

                android:label="_Points">

            <intent-filter>

                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />

            </intent-filter>

        </activity>



        <activity

                android:name="Transform3dActivity"

                android:label="_3d">