Method isVisible

CodenameOne/src/com/codename1/ui/Graphics.java:433–488

(int x, int y, int w, int h)

    ///
    /// true if the rectangle intersects the current clip
    public boolean isVisible(int x, int y, int w, int h) {
        if (w <= 0 || h <= 0) {
            return false;
        }
        int cx = getClipX();
        int cy = getClipY();
        int cw = getClipWidth();
        int ch = getClipHeight();
        if (cw <= 0 || ch <= 0) {
            return false;
        }
        // If a non-trivial transform is in effect, map the rectangle's corners
        // through it and test the resulting bounding box. Only the matrix is
        // applied -- the integer translate cancels against getClipX/getClipY,
        // which already subtract it back out.
        if (isTransformSupported()) {
            Transform t = getTransform();
            if (t != null && !t.isIdentity()) {
                try {
                    float[] pts = new float[]{
                            x, y,
                            x + w, y,
                            x + w, y + h,
                            x, y + h
                    };
                    t.transformPoints(2, pts, 0, pts, 0, 4);
                    float minX = pts[0];
                    float maxX = pts[0];
                    float minY = pts[1];
                    float maxY = pts[1];
                    for (int i = 2; i < pts.length; i += 2) {
                        float px = pts[i];
                        float py = pts[i + 1];
                        if (px < minX) {
                            minX = px;
                        }
                        if (px > maxX) {
                            maxX = px;
                        }
                        if (py < minY) {
                            minY = py;
                        }
                        if (py > maxY) {
                            maxY = py;
                        }
                    }
                    return minX < cx + cw && minY < cy + ch && maxX > cx && maxY > cy;
                } catch (RuntimeException err) {
                    // Some ports throw when the transform isn't backed natively;
                    // fall back to the untransformed rectangle test below.
                    Log.e(err);
                }
            }
        }
        return x < cx + cw && y < cy + ch && x + w > cx && y + h > cy;
    }

    /// Clips the given rectangle by intersecting with the current clipping region, this