0.16 - 4 new powerful box selection actions & more

In this video, i'm highlighting some of the most important feature additions in this new version. 

There's quite a bit more though - be sure to check the changelog. 

Edit: included it here for convenience:

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0.16

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New features:

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New Drag Selection actions: 

These 4 actions work equally on the tileset and screen canvas:

• Move selection box: within selection; shift + right mouse, then begin drag.
• Swap tiles: within selection; right mouse, begin drag.
• Move tiles: within selection; right mouse, begin drag, hold ctrl. 
• clone tiles: within selection; right mouse, begin drag, hold ctrl+shift.

These three are signified by the white selection box staying in place; while a gray "destination box" gets dragged around.

Dropping the destination box above the selection box cancels the action. 

"Scan" with active tile cursor:

• With a simple left-click on the tileset, if you begin dragging, you'll "scan" the tileset; dragging the "Active tile cursor" along.
• This is a useful alternative method for navigating the CHR Editor quickly. 
• Combined with the toggle button "Selected only", it's also an effective method to get a better understanding of how tiles are used and in what quantity on the screen canvas. 

Show/Hide pixel grid (CHR Editor): 

• Toggles the grid on/off in the CHR Editor.
• Shortcut: [Ctrl+G]

Improvements & fixes:

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Box selections stay positive:

• Expanding a box selection north or west would invert the selection coordinates which was slightly iffy and had many workarounds under the hood to prevent further weirdness.

• Now, selections remain "positive" no matter which direction you drag it; keeping the origin coordinate stable.  

CHR Editor pixel grid now easier on the eyes: 

• In the environment where NEXXT is made, the canvas which the CHR editor is painted on relied on a MS Windows-controlled theme. This worked well enough up until windows 7 in classic mode, but in later OSes like win 10 (i haven't tested win 11), this background & grid  colour was too sharp. It's now set to an absolute colour of #CFCFCF which is easier to look at when its grid is on. 

Find/Remove unused bug:

• Discovered and resolved a NESST-old bug where the tool would not detect if tile 0xFF was unused, because that's the initial tile value of all 64 entries to all 256 metasprite lists. Now fixed by ignoring sprite list items of unused status (this is signified by a relative Y position value of 0xFF as well).

Ctrl+X/Ctrl+V bug:

• In the context of the metasprite editor, These actions would often delete and forget CHR tiles in addition to working on metasprites. This is now fixed and each works respectively on the context of what was last clicked on, as was the intention. 

View Selected Only bug:

• Now correctly displays selection while the CHR editor is in 2x2 edit mode.

Swap Pattern tables in selection [Ctrl+Alt+X] improvement:

• Now accepts multi-selected tiles (ctrl+click)
• Now properly sets Undo.

Tileset tab:

• Double clicking on the big tileset now correctly opens the CHR editor.

Swap tiles - now in plural:

• It's now possible to swap a box selection of tiles.
• In 2x2 edit mode, you automatically swap a 2x2 constellation of tiles by this action. 
• The destination of the tile swap is now clearly displayed with a gray "destination box" around the cursor. (right mouse button + begin drag)

Status readout:

• The readout now updates smoother while moving the cursor over the screen canvas. 

CPU overuse bug:

• the cpu ran needless routines continuously when holding alt or ctrl+alt, which contributed to lag when working on the screen canvas. Now fixed. 

Errata:

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As of 0.15, window forms now snap to the edges of your screen. I forgot to include this in the changelog.