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OpenGL SL - Devide camera view

make image pattern


How can we devide camera view like above image? If you think adjusting the position and size by dividing each section, it will be a very difficult task. And If you made it that way, how can you make the following 10x10 image?

multiply image pattern


The answer is

"To make pattern, Use fract function."

The full code is like below. 
If you want to make 4x4 image, change this line : " uv *= 4.0; "


void mainImage( out vec4 fragColor, in vec2 fragCoord ){
    // Normalized pixel coordinates (from 0 to 1)
    vec2 uv = fragCoord/iResolution.xy;
    uv *= 10.0;
    uv = fract(uv);
    fragColor = texture(iChannel0, uv);
}


Declaration
genType fract( genType x )

 Description
returns the fractional part of x. This is calculated as x - floor(x).

 reference ( https://www.khronos.org/registry/OpenGL-Refpages/gl4/html/fract.xhtml )
- Before fract function
- After fract function
how fract function work

(y-ax is same to x-ax)
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