D27788: Implement EGL_KHR_partial_update and EGL_EXT_swap_buffers_with_damage

zzag added inline comments.

INLINE COMMENTS

> egl_gbm_backend.cpp:441
>  
> +static QVector<EGLint> regionToRects(const QRegion &lastRegion, int height)
> +{

s/lastRegion/region/

> egl_gbm_backend.cpp:465
> +    {
> +        const QRegion region = (output.pendingDamagedRegions() | damagedRegion)
> +                                    & output.output->geometry();

`damagedRegion` contains the region that will be repainted in the next frame, so we don't need to accumulate surface damages again.

I suppose we want something like

  const QRegion region = damagedRegion & output.output->geometry();

> egl_gbm_backend.cpp:472
> +        if (!correct) {
> +            qCritical() << "failed eglSetDamageRegionKHR" << eglGetError();
> +        }

Use categorized logging please. Also, it's not a critical error if eglSetDamageRegionKHR() fails. qCWarning(KWIN_DRM) would be a better choice.

> egl_gbm_backend.cpp:529-541
> +QRegion EglGbmBackend::Output::pendingDamagedRegions() const
> +{
> +    QRegion region;
> +    // Note: An age of zero means the buffer contents are undefined
> +    if (bufferAge > 0 && bufferAge <= damageHistory.count()) {
> +        for (int i = 0; i < bufferAge - 1; i++)
> +            region |= damageHistory[i];

I think we can drop this method now since only EglGbmBackend::prepareRenderingForScreen() needs to accumulate damage.

REPOSITORY
  R108 KWin

REVISION DETAIL
  https://phabricator.kde.org/D27788

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