scale not correctly updated on pdf-viewer rotation for pdf page with 90° rotation

[QuentinChaumont]

Bug Report or Feature Request (mark with an x)

- [ ] Regression (a behavior that used to work and stopped working in a new release)
- [x] Bug report -> please search issues before submitting
- [ ] Feature request
- [ ] Documentation issue or request

Hi, first of all thanks for your work.

Configuration of pdf-viewer :

[original-size]="false"
[page]="pageNumber"
[render-text]="true"
[show-all]="false"
[rotation]="rotation"
[show-borders]="false"
[src]="src"
[zoom-scale]="'page-width'"

Description of the issue :

When I'am using a pdf with pages already rotated on pdf-viewer it display perfectly.
But when I apply a pdf-viewer rotation of 90° on it the width scale is not updated. So my pdf succesfully rotate but it is cropped because width scale did not update.

Resolution of the issue :

I managed to find the reason on pdf-viewer.component.ts line 323 :
const rotation = this._rotation || page.rotate;
The fix is simple :
const rotation = this._rotation + page.rotate;

Explanation of the fix :

Without fix : const rotation = this._rotation || page.rotate; :

1 - pdf page with rotation already applyed on it is loaded
2 - const rotation = 90 (from page.rotate) ✔️
3- I apply pdfViewer rotation on it
4- const rotation = 90 (from this._rotation) ❎

With fix : const rotation = this._rotation + page.rotate; :

1 - pdf page with rotation already applyed on it is loaded
2 - const rotation = 90 (from this._rotation 0 + page.rotate 90 ) ✔️
3- I apply pdfViewer rotation on it
4- const rotation = 180 (from this._rotation 90 + page.rotate 90 ) ✔️

I'm doing pull request to fix this for you.

Have a good day

[VadimDez]

@QuentinChaumont thanks for the PR! i've just tested and see no difference before and after applying your changes. Can you please make some screenshots showing the difference before vs after?

[QuentinChaumont]

It's a very specific use-case appear only with pdf saved with internal rotation in some pages.

For normal pdf pages without internal rotation (page.rotation) it's work fine with 90° rotation and zoom-scale= 'page-width' the pdf resize to take all the width space :

When I go to the third page of my pain in the ass pdf which has an internal rotation (page.rotation = 90), you can see that the pdf does not resize to use full width :

After my quick fix, behaviour does not change normal pages rotation but fix the pages with internal rotation :

[QuentinChaumont]

If you want to try by yourself i give you my pdf :

• first and second page are normal
• third pages has internal page rotation of 90° (it's created the problem)

last-page-rotated-anonyme.pdf

[QuentinChaumont]

Thx for your time.

[VadimDez]

Thanks @QuentinChaumont, I could replicate the issue with your PDF, will publish 9.1.5 soon