Pinch zooming speed gets faster when page width gets smaller than view width

[dhruvhighspot]

It seems that the animation for zooming in is scaling a lot in landscape mode - causing a small pinch to zoom a lot.

https://github.com/espresso3389/pdfrx/assets/156050023/33cb555f-09e1-4258-8fa9-82b5bc2f66c6

[dhruvhighspot]

@espresso3389 Hey, can you fix this? Zoom is a little bit fast and/or not smooth.

[espresso3389]

Ah, zoom suddenly gets speed-up when the page width gets smaller than the screen width. It occurrs not only on landscape mode but also on portrait mode The sample's page 3 has the same issue...

[espresso3389]

I could not determine the mechanism behind the behavior so far.

[dhruvhighspot]

Please prioritize the task and fix it as soon as possible.

[edwinkomalaICI]

Hi, is there any fixing or workaround? I have the same issue

[srinivasghighspot]

Could you please share the fix?

[jeffpontocom]

Maybe the bug is the normalizeMatrix pre-settings. I set the bellow code and zoom gets smooth, but the viewer do not respect the document limits and the user can slide the pdf out of the viewer.

normalizeMatrix: (matrix, viewSize, layout, controller) => matrix, @espresso3389 can you check this?

[jeffpontocom]

Maybe the bug is the normalizeMatrix pre-settings. I set the bellow code and zoom gets smooth, but the viewer do not respect the document limits and the user can slide the pdf out of the viewer.

normalizeMatrix: (matrix, viewSize, layout, controller) => matrix, @espresso3389 can you check this?

Actually I found out a great solution using the normalize example in documentation: The problem is in the z axis of the third line in controller.calcMatrizFor method that always return 1.0. I just change the result matrix with .scaled(1.0,1.0,newzoom).

// before [0] zoom, 0.0, 0.0, X axis [1] 0.0, zoom, 0.0, Y axis [2] 0.0, 0.0, 1.0, 0.0 [3] 0.0, 0.0, 0.0, 1.0

// after .scaled method [0] zoom, 0.0, 0.0, X axis [1] 0.0, zoom, 0.0, Y axis [2] 0.0, 0.0, zoom, 0.0 [3] 0.0, 0.0, 0.0, 1.0

// code // (do not forget to copy the extension on num [_RangeDouble] to use the range method.)

normalizeMatrix: (matrix, viewSize, layout, controller) {
                // If the controller is not ready, just return the input matrix.
                if (controller == null || !controller.isReady) return matrix;
                final newValue = Matrix4.copy(matrix);
                final position = newValue.calcPosition(viewSize);
                final newZoom = controller.params.boundaryMargin != null
                    ? newValue.zoom
                    : max(newValue.zoom, controller.minScale);
                final hw = viewSize.width / 2 / newZoom;
                final hh = viewSize.height / 2 / newZoom;
                final x = position.dx.range(hw, layout.documentSize.width - hw);
                final y =
                    position.dy.range(hh, layout.documentSize.height - hh);
                return controller
                    .calcMatrixFor(Offset(x, y),
                        zoom: newZoom, viewSize: viewSize)
                    .scaled(1.0, 1.0, newZoom);
              },

extension _RangeDouble<T extends num> on T {
  /// Identical to [num.clamp] but it does nothing if [a] is larger or equal to [b].
  T range(T a, T b) => a < b ? clamp(a, b) as T : (a + b) / 2 as T;
}

[espresso3389]

Very interesting. I'll check it later.

[dhruvhighspot]

@espresso3389 please fix this asap

[espresso3389]

1.1.27 applies the proposed fix by @jeffpontocom but I' not sure if it works well or not. Personally, I don't feel any difference...

[Reyrey14-1]

1.1.27 applies the proposed fix by @jeffpontocom but I' not sure if it works well or not. Personally, I don't feel any difference...

works great! thank you guys!