Enhancement : Easy way to move the viewport

[juliandescottes]

From suggestion on http://www.reddit.com/r/gamedev/comments/28uxd9/piskel_new_online_pixel_art_app_for_creating/

When zoomed in, have a convenient way of moving the viewport, such as :

• hold middle button + move
• (something else for touchpads ? keyboard key to hold while doing a mouse move ?)

[captainbrosset]

For what it's worth, photoshop has a hand/move tool, easily accessed via the 'H' shortcut. I use it all the time when zoomed in. Middle-click sounds good too, if it's not needed for other tools.

[grahammutter]

I'm going to try to implement this on monday+tuesday

[juliandescottes]

@gdot5 Cool !

You can start looking at pskl.controller.DrawingController, that's where all mouse events for the drawing zone are handled.

Let us know if you need help !

[grahammutter]

I like having the middle mouse button for the color-picker. Maybe holding both mouse_buttons down while moving the mouse the mouse would be a good alternative?

[juliandescottes]

I also want to keep the middle button click for the color picker, I use it all the time.
Technically I think we could support both.

Right now the color-picking is bound to a mousedown event I think. We could move it to the mouseup and have the following logic :

• if mousedown + mouseup occured on the same pixel : colorpicker
• if the user drags the mouse after the mousedown and leaves the pixel of the mousedown : start moving the viewport

So it's feasible, a prototype to see if it's easy to use would be nice.

Otherwise, we can :

• create a new tool to move the viewport.Would only be useful when zoomed in, not sure it's worth the extra UI
• use a metakey + primary/secondary button, but we already have several tools using ctrl or shift ... this leaves only alt available, but I want to keep it for tools in the future
• use a metakey + middle button : at least there's no conflict with anything else, quite easy to prototype

From this list I like two options :

• support both color picker + move viewport on middle button, with the logic I described above
• use a metakey + middle button

[je2mz]

Yes, I think this is a must!

[juliandescottes]

Implemented via middle mouse button in 0.4.0