#version 450

layout (binding = 1) uniform sampler2D samplerColor;
layout (binding = 2) uniform sampler2D samplerColor_ex;

layout (location = 0) in vec2 inUV;
layout (location = 1) in vec3 inNormal;


layout (location = 0) out vec4 outFragColor;

void main() 
{
	vec4 color = texture(samplerColor, inUV);
	vec4 color_ex = texture(samplerColor_ex, inUV);

	vec3 N = normalize(inNormal);

	vec4 textureColor = color;

	//if (textureColor.a < 0.1) 
	//{
        //textureColor = vec4(0.2, 0.2, 0.2, 0.5); 
	//	discard;
    //}

	// 计算与 (0,0,1) 的点乘
    float ndot = dot(N, vec3(0.0, 0.0, -1.0));

	// 保证结果 >= 0
    ndot = max(ndot, 0.0);
	
	vec4 blendedColor = mix(color_ex, color, ndot);

	outFragColor = blendedColor;

//	outFragColor = vec4(1, 0, 0, 1);
}