Do universal vertex and fragment shaders exist for game engines?

[alexlee]

I want to build a basic 2D game engine that might expand to 3D later. I’ve been looking at how other engines handle shaders and noticed they use specific shaders for different effects plus a basic projection matrix shader. Most other work happens in regular JavaScript code.

gl_Position = viewMatrix * transform * vec4(vertexPos, 1.0);

I’m wondering if platforms that let you create complex visual effects using only shaders are just for experimentation. Do actual game engines require lots of custom shader code for different features? Can I use one standard shader setup for everything in my engine, or do I need separate shaders for each rendering task?

I’m trying to figure out if there’s a single core shader that can handle all rendering needs for a fast 2D WebGL engine. I’d rather find this fundamental shader approach instead of creating new shaders for every different situation.

Here’s an example of a basic vertex shader structure:

attribute vec2 vertexPos;
attribute vec2 texCoords;

uniform mat3 viewMatrix;

varying vec2 fragTexCoords;

void main(void)
{
    gl_Position = vec4((viewMatrix * vec3(vertexPos, 1.0)).xy, 0.0, 1.0);
    fragTexCoords = texCoords;
}

Is this kind of simple approach enough for most 2D rendering tasks?

[AdventurousHiker17]

your basic vertex shader works fine for most 2D stuff, but it won’t handle everything forever. I tried the same thing and quickly needed separate shaders for lighting effects and post-processing. The real trick is designing your engine so swapping shaders doesn’t hurt performance - batch everything by shader type first, then render. your example looks good for simple quad rendering tho.

[ameliat]

Built a 2D engine that went 3D - the “universal shader” thing works but has limits. Your vertex shader handles basic transforms fine, but fragment shaders are where it gets messy. Even simple 2D games need different fragment processing for UI vs sprites vs backgrounds. I ended up with 2-3 base shaders using preprocessor directives instead of one massive uber-shader. Way more maintainable. Here’s the thing: WebGL shader compilation is cheap, but switching between programs during rendering kills performance. Skip the universal shader. Build a small family that shares vertex processing but handles different fragment operations. This scaled way better when I added color tinting, alpha blending, and texture effects. Performance difference between 1 shader and 3-4 specialized ones? Basically nothing if you batch your draw calls right. Your current vertex shader looks solid for 2D - just get ready for fragment shader variations as you add features.

[scarlettturner]

I’ve worked on something similar and can share what I learned. You can use one universal shader for basic 2D rendering, but you’ll hit performance and functionality walls fast as your engine grows. Your vertex shader works fine for simple textured quads, but even basic 2D games need specialized shaders. Think sprite animations with texture atlases, particle systems, or basic lighting. I started with the single shader mindset too but ended up with 4-5 specialized shaders in just a few months. For a 2D WebGL engine, start with your universal approach but make your shader system modular from day one. Use uniform flags to toggle different rendering modes in the same shader program - gives you flexibility without constantly switching programs. The real bottleneck isn’t multiple shaders, it’s state changes between them. Modern engines batch rendering calls by shader type to minimize switches. Your simple approach works initially, but plan for shader variants early or you’ll face major refactoring later.