* Adds pkg/savegame to store user progress thru Level Packs.
* The savegame.json is mildly tamper resistant by including a checksum
along with the JSON body.
* The checksum combines the JSON string + an app secret (in savegame.go)
+ user specific entropy (stored in their settings.json). If the user
modifies their save file and the checksum becomes invalid the game
will not load the save file, acting like it didn't exist, resetting
all their high scores.
Updates to the Story Mode window:
* On the LevelPacks list: shows e.g. "[completed 0 of 3 levels]" showing
a user's progress thru the level pack.
* Below the levels on the Detail screen:
* Shows an indicator whether the level is completed or not.
* Shows high scores (fastest times beating the level)
* Shows a padlock icon if levels are locked and the player hasn't
reached them yet. Pops up an Alert modal if a locked level is
clicked on.
Scoring is based around your fastest time elapsed to finish the level.
* Perfect Time (gold coin): player has not died during the level.
* Best Time (silver coin): player has continued from a checkpoint.
In-game an elapsed timer is shown in the top left corner along with the
gold or silver coin indicating if your run has been Perfect.
If the user enters any Cheat Codes during gameplay they are not eligible
to win a high score, but the level will still be marked as completed.
The icon next to the in-game timer disappears when a cheat code has been
entered.
* Add initial Ellipse Tool to the Editor Mode. Currently there's
something wrong with the algorithm and the ellipses have a sort of
'lemon shape' to them.
* Refactor the IterLine/IterLine2 functions to be more consistent.
IterLine used to be the raw algorithm that took a bunch of coordinate
numbers and IterLine2 took two render.Point's and was the main one
used throughout the app. Now, IterLine takes the two Points and the
raw algorithm function removed.
* Implement Brush Sizes for drawtool.Stroke and add a UI to the tools panel
to control the brush size.
* Brush sizes: 1, 2, 4, 8, 16, 24, 32, 48, 64
* Add the Eraser Tool to editor mode. It uses a default brush size of 16
and a max size of 32 due to some performance issues.
* The Undo/Redo system now remembers the original color of pixels when
you change them, so that Undo will set them back how they were instead
of deleting the pixel entirely. Due to performance issues, this only
happens when your Brush Size is 0 (drawing single-pixel shapes).
* UI: Add an IntVariable option to ui.Label to bind showing the value of
an int reference.
Aforementioned performance issues:
* When we try to remember whole rects of pixels for drawing thick
shapes, it requires a ton of scanning for each step of the shape. Even
de-duplicating pixel checks, tons of extra reads are constantly
checked.
* The Eraser is the only tool that absolutely needs to be able to
remember wiped pixels AND have large brush sizes. The performance
sucks and lags a bit if you erase a lot all at once, but it's a
trade-off for now.
* So pixels aren't remembered when drawing lines in your level with
thick brushes, so the Undo action will simply delete your pixels and not
reset them. Only the Eraser can bring back pixels.
* Toolbar has icon buttons for the Pencil Tool, Line Tool, Rect Tool,
Actor Tool and Link Tool.
* Remove the tab buttons from the top of the Palette window. The palette
tab is now toggled between Swatches and Doodads by the tool selected
on the tool bar, instead of the tab buttons setting the tool.
* Remove the "Link Doodads" button from the Doodad Palette. The Link
Tool has its own dedicated toolbar button with the others.
Noah