Convert CameraPreview widget to Texture widget

I wanna display camera view on whole screen - without stretched and unnecessary zoom.

I have code like that:

Transform.scale(
                scale: 1.7,
                child: Center(
                  child: CameraPreview(controller!),
                ),
              )

It view great - exactly as I would like, but I have to have Texture widget instead CameraPreview, but if I can code:

Transform.scale(
              scale: 1.7,
              child: Center(
                child: Texture(textureId: textureId),
              ),
            )

preview is on whole screen (success) but is very zoomed.

I create texture in this way:

private TextureRegistry.SurfaceTextureEntry primaryTexture;
Surface primarySurface = new Surface(this.primaryTexture.surfaceTexture());