如何让一个特殊的SurfaceView只绘制部分区域？

[zero15]

这个SurfaceView是被用来显示摄像头的Preview的，不知道有什么办法可以裁剪这个SurfaceView

[hn_刘潇]

matrix

[hn_刘潇]

引用 1 楼 x13945 的回复:

matrix

    /**
     * <p>Sets the transform to associate with this texture view.
     * The specified transform applies to the underlying surface
     * texture and does not affect the size or position of the view
     * itself, only of its content.</p>
     * 
     * <p>Some transforms might prevent the content from drawing
     * all the pixels contained within this view's bounds. In such
     * situations, make sure this texture view is not marked opaque.</p>
     * 
     * @param transform The transform to apply to the content of
     *        this view.
     * 
     * @see #getTransform(android.graphics.Matrix) 
     * @see #isOpaque() 
     * @see #setOpaque(boolean) 
     */
    public void setTransform(Matrix transform) {
        mMatrix.set(transform);
        mMatrixChanged = true;
        invalidateParentIfNeeded();
    }

[zero15]

引用 2 楼 x13945 的回复:

[quote=引用 1 楼 x13945 的回复:] matrix

    /**
     * <p>Sets the transform to associate with this texture view.
     * The specified transform applies to the underlying surface
     * texture and does not affect the size or position of the view
     * itself, only of its content.</p>
     * 
     * <p>Some transforms might prevent the content from drawing
     * all the pixels contained within this view's bounds. In such
     * situations, make sure this texture view is not marked opaque.</p>
     * 
     * @param transform The transform to apply to the content of
     *        this view.
     * 
     * @see #getTransform(android.graphics.Matrix) 
     * @see #isOpaque() 
     * @see #setOpaque(boolean) 
     */
    public void setTransform(Matrix transform) {
        mMatrix.set(transform);
        mMatrixChanged = true;
        invalidateParentIfNeeded();
    }

[/quote] 能麻烦讲得详细点么，怎么样才能达到裁剪的效果，我只知道矩阵可以处理纹理的各种效果，可不知道怎么裁剪掉surfaceView的一部分不进行绘制啊

[zero15]

引用 2 楼 x13945 的回复:

[quote=引用 1 楼 x13945 的回复:] matrix

    /**
     * <p>Sets the transform to associate with this texture view.
     * The specified transform applies to the underlying surface
     * texture and does not affect the size or position of the view
     * itself, only of its content.</p>
     * 
     * <p>Some transforms might prevent the content from drawing
     * all the pixels contained within this view's bounds. In such
     * situations, make sure this texture view is not marked opaque.</p>
     * 
     * @param transform The transform to apply to the content of
     *        this view.
     * 
     * @see #getTransform(android.graphics.Matrix) 
     * @see #isOpaque() 
     * @see #setOpaque(boolean) 
     */
    public void setTransform(Matrix transform) {
        mMatrix.set(transform);
        mMatrixChanged = true;
        invalidateParentIfNeeded();
    }

[/quote] 有办法在摄像头把预览图渲染到surfaceView上之前把数据改掉么。。。

[Birds2018]

用GLSurfaceView Render,回调函数里面用OpenGL 去处理 想怎么处理都能弄。