#version 410

uniform sampler2D texture1;
in vec2 uvV;

out vec4 fragColor;
uniform float opacity = 1.0;

// Simplest Texture render -- assign "texture1" from varying UV coords.
// Requires vertex shader with uvV output, only.
void main (void)
{
    fragColor = texture(texture1, uvV);
    fragColor = vec4(fragColor.rgb, opacity);
}