Kingmaker - Alpha 2 and Graphics Rendering

Pathfinder: Kingmaker has a new update that explains in detail its graphics rendering technology and announces Alpha 2.

Dear Pathfinders,

It's time for another peek behind the curtains. Today's update is all about lighting, shaders, floral dispersion and all those fun details and effects, which add a bit more life to our game world. Before we get all technical and start revealing our tricks, though, we have two announcements. First of all: the stage 2 alpha test is nearly here!

Our next big alpha build is almost ready and will be distributed as an update through Steam to all alpha testers today. What does this mean for you? If you're one of our alpha testers, you'll be getting more content, more gameplay features, more companions and more Pathfinder: Kingmaker to play. If you aren't part of the alpha, you'll be happy to hear that we're well on schedule, development is steadily progressing and there should be streams and videos of the new build popping up for your viewing pleasure in the near future. Keep your eyes peeled!

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Now, let's talk more about graphics in Kingmaker. We've already told you about our water rendering techniques. Today we'll review a few other graphics features of our project.

Strange as it may sound, graphics development starts with market research. At an early development stage, we researched the stats of video cards on the market and chose our target hardware in order to let as many players as possible experience all graphical content we produce. Then we selected rendering technologies that would be perfect for this hardware. A lighting system is the basis of game rendering, unless the game is match3 with abstract graphics. The lighting system determines the graphics pipeline architecture of a frame, so we'll start with that.

Forward rendering

There are 2 basic approaches to real-time lighting calculations:

• Forward rendering
• Deferred shading

And of course, there are a lot of variations and combinations of these.

Forward rendering is the most widely-used (and probably the first) technique for calculating lighting in real time in games. A model consisting of vertices is fed to the vertex shader, where its vertices are transformed to screen space, and all this data is passed down the video card pipeline to the pixel shader, where lighting happens. This is called forward rendering with per-pixel lighting. 

Of course, lighting can be calculated in the vertex shader as well, then it will be forward rendering with vertex lighting. Vertex lighting is less GPU intensive, because there are much fewer vertices than there are pixels, but its visual quality is also lower. 

Usually shaders that perform calculations only work with one light source. But objects may be lit by multiple sources at the same time. This means the object must be rendered as many times as there are sources that light it. This is the most significant flaw of forward rendering.

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