one way to automatically flip texture co-ordinates in GLSL

textureFlipped.glsl

#version 300 es

precision mediump float;
precision mediump sampler2D;
precision mediump sampler3D;

vec4 textureFlipped(sampler2D s, vec2 coords) {
    return texture(s, vec2(coords.x, 1.0 - coords.y));
}
vec4 textureFlipped(sampler3D s, vec3 coords) {
    return texture(s, vec3(coords.x, 1.0 - coords.y, coords.z));
}
#define texture textureFlipped

uniform sampler2D someTex;
in vec2 texCoords;
out vec4 fragColor;

void main(void) {
    fragColor = texture(someTex, texCoords);
}