WorkspaceGridRenderer.java 文件源码

/**
 * Using the current view scale, create a bitmap tiling shader to render the workspace grid.
 */
void updateGridBitmap(float viewScale) {
    int gridSpacing = (int) (GRID_SPACING * viewScale);

    // For some reason, reusing the same Bitmap via Bitmap.reconfigure() leads to bad rendering,
    // so recycle existing Bitmap and create a new one instead.
    if (mGridBitmap != null) {
        mGridBitmap.recycle();
    }
    mGridBitmap = Bitmap.createBitmap(gridSpacing, gridSpacing, Bitmap.Config.ARGB_8888);

    Canvas bitmapCanvas = new Canvas(mGridBitmap);
    bitmapCanvas.drawCircle(GRID_RADIUS, GRID_RADIUS, GRID_RADIUS, mCirclePaint);

    mGridPaint.setShader(
            new BitmapShader(mGridBitmap, Shader.TileMode.REPEAT, Shader.TileMode.REPEAT));
}