Arrays & shaders: heatmaps in Unity

This tutorial explains how to pass arrays to shaders in Unity. This feature has been present for a long time, but is mostly undocumented. Unity 5.4.0 Beta 1 will introduce a proper API to pass arrays to shaders; this technique however will work with any previous version.

If you are using Unity 5.4+, please refer to the Arrays & Shaders in Unity 5.4+ tutorial.

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How to Snap to Grid in Unity3D

Despite Unity3D being such an advanced framework, I am sometimes puzzled by its lack of basic features. Especially when working with 2D games, the lack of a proper snap to grid option is simply crazy. Luckily, Unity3D allows to extend its basic interface to add new behaviours. This post will explain how to add a customisable snap to grid option to your objects. Two different implementations are presented; the first one, despite being more complicated, could be used a good starting point to further extend and customise the inspector.

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Screen shaders and image effects in Unity3D

Part 1, Part 2, Part 3, Part 4, Part 5, [download the Unity3D package]

If you are using Unity3D you may be familiar with image effects. They are scripts which, once attached to a camera, alter its rendering output. Despite being presented as standard C# scripts, the actual computation is done using shaders. So far, materials have been applied directly to geometry; they can also be used to render offscreen textures, making them ideal for postprocessing techniques. When shaders are used in this fashion, they are often referred as screen shaders.

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Vertex and fragment shaders in Unity3D

Part 1, Part 2, Part 3, Part 4, Part 5, [download the Unity3D package]

The previous three posts of this tutorial have introduced surface shaders and how they can be used to specify physical properties (such as albedo, gloss and specular reflections) of the materials we want to model. The other type of shader available in Unity3D is called vertex and fragment shader. As the name suggests, the computation is done in two steps. Firstly, the geometry is passed through a function called (typically called vert) which can alter the position and data of each vertex. Then, the result goes through a frag function which finally outputs a colour.

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A gentle introduction to shaders in Unity3D

Part 1, Part 2, Part 3, Part 4, Part 5

We can safely say that Unity3D has made game development easier for a lot of people. Something where it still has a long way to go is, with no doubt, shader coding. Often surrounded by mystery, a shader is a program specifically made to run on a GPU. It is, ultimately, what draws the triangles of your 3D models. Learning how to code shaders is essential if you want to give a special look to your game. Unity3D also uses them for postprocessing, making them essential for 2D games as well. This series of posts will gently introduce you to shader coding, and is oriented to developers with little to no knowledge about shaders.

Introduction

The diagram below loosely represents the three different entities which plays a role in the rendering workflow of Unity3D:

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