Simple intersection checking between rotated rectangles and circles/points

(click to interact)Intersection checking between rotated rectangle and point/circle
(mouseover/click to play GIF) (click and drag to adjust rectangle size/position/rotation; distance to a circle is shown)

Suppose you have a rotated rectangle and a basic shape that rotation doesn't matter for (such as a point, circle, or a line segment), and you want to check whether the two are intersecting - be that for collision handling, hit testing, or whatever else.

On a glance this might seem like a bother because things are rarely too simple with rotated rectangles, but in this case it isn't - because you can "unrotate" the rectangle.

This small post is about that.

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2d pivot points explained

(click to interact)Explaining pivot points
(mouseover/click to play GIF) (spaceship graphic by Kenney)

Nowadays, most development tools provide ways of setting pivot/center point for imagery - that is, the relative point around which the image will rotate and usually be positioned relative to.

However, ability to define multiple pivot points per image remains relatively uncommon, despite being something that you want to have projectiles fire from a correct point of a sprite, display weapons/attachements at right relative points, or do anything else that demands relative offsets.

This small post is about that.

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GameMaker: Simplest possible custom timelines

This post is about implementing custom timelines in GameMaker.

Admittedly, timelines remain to be one of the more dated features of the software, designed for a specific purpose and kept in their original form for compatibility.

Time to time you'll see someone stopping by on forums to write a big rant about how these are a mess, do not do what they expect them to do, and should be redesigned immediately.
People will usually also argue that doing these things by yourself is too hard.

Since it is far easier than people claim, I decided to write a post about this.

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Setting up portrait orientation on Wacom One / Intuos / Bamboo

This post is about modifying configuration files for Wacom drivers to have a Wacom One tablet function in portrait orientation despite the option not being exposed in configuration UI.

Update: apparently the same applies to Intuos and Bamboo product lines, likely for the entire "generation" of tablets using the same drivers.

Update 2: for One/Intuous, the newer version of driver (6.x) has these options exposed in UI.

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GameMaker: Clipping drawn graphics


Mouseover to activate, click to reposition the clipping star.

This is a tutorial about pretty much everything related to clipping drawn graphics in GameMaker.

That is, having drawn graphics only display inside a certain ("clip") area, be that a rectangle (UI regions, minimaps, etc.), circle, or a completely arbitrary shape (pictured above).

Also I'm trying new things so this post is nicely stuffed with interactive demos and snippets.

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