How to Flip Left/Right an qml Item in shader？

[dhuta]

As asked above, the problem is that my fixed version shader (from Qt5.4.2 example called tweetsearch, which is up/down flip) does not work well for the second source item.

my version just change some shader code:

fragmentShader: "
        uniform lowp float qt_Opacity;
        uniform sampler2D sourceA;
        uniform sampler2D sourceB;
        uniform highp float delta;
        varying highp vec2 qt_TexCoord0;
        void main() {
//                highp vec4 tex = vec4(qt_TexCoord0.x, qt_TexCoord0.y * 2.0,      qt_TexCoord0.x, (qt_TexCoord0.y-0.5) * 2.0);

            // TODO: How?
            highp vec4 tex = vec4(qt_TexCoord0.x * 8.0, qt_TexCoord0.y, (qt_TexCoord0.x + 1.0), (qt_TexCoord0.y-0.5) * 2.0);

            highp float shade = clamp(delta*2.0, 0.5, 1.0);
            highp vec4 col;
            if (qt_TexCoord0.x < 0.5) {
                col = texture2D(sourceA, tex.xy) * (shade);
            } else {
                col = texture2D(sourceB, tex.wz) * (1.5 - shade);
                col.w = 0.50;
            }
            gl_FragColor = col * qt_Opacity;
        }
    "
    property real h: width
    vertexShader: "
    uniform highp float delta;
    uniform highp float factor;
    uniform highp float h;
    uniform highp mat4 qt_Matrix;
    attribute highp vec4 qt_Vertex;
    attribute highp vec2 qt_MultiTexCoord0;
    varying highp vec2 qt_TexCoord0;
    void main() {
        highp vec4 pos = qt_Vertex;
        if (qt_MultiTexCoord0.x == 0.0)
            pos.y += factor * (1. - delta) * (qt_MultiTexCoord0.y * -2.0 + 1.0);
        else if (qt_MultiTexCoord0.x == 1.0)
            pos.y += factor * (delta) * (qt_MultiTexCoord0.y * -2.0 + 1.0);
        else
            pos.x = delta * h;
        gl_Position = qt_Matrix * pos;
        qt_TexCoord0 = qt_MultiTexCoord0;
    }"

Could anyone help me out? Thanks.