Thank you for the detailed description. It looks like these are two separate issues.
About the DrawTextTool
- the difference between the preview and the result is not expected. We have logged this bug and we will try to fix it in one of the next official releases.
About the SharpenTool
- the difference between the preview and the result is due to the fact that the preview uses a shapen shader effect on a copy of the image in the preview panel to show the results of the effect in real time. However, the preview panel is scaled depending on the current zoom level, but when the tool actually applied - the shader is always executed on the image in its original size. The shapen tool can have slight variations in the result based on the scale of the image - so this is what you have noticed. The preview of the ShapenTool is accurate if the scale factor of the image editor is 100%.
I hope that was helpful.
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