#version 450

layout(location = 0) in vec3 fragPosition;
layout(location = 1) in vec4 fragWeights;
layout(location = 2) in vec2 fragUV;

layout(binding = 1) uniform sampler2DArray terrainTexArray;

layout(location = 0) out vec4 outColor;

void main() {
    vec4 colorGrass = texture(terrainTexArray, vec3(fragUV, 0.0)); // Index 0
    vec4 colorRock  = texture(terrainTexArray, vec3(fragUV, 1.0)); // Index 1
    vec4 colorSand  = texture(terrainTexArray, vec3(fragUV, 2.0)); // Index 2
    vec4 colorMud   = texture(terrainTexArray, vec3(fragUV, 3.0)); // Index 3

    vec4 dynamicTerrainColor =
    (colorGrass * fragWeights.r) +
    (colorRock  * fragWeights.g) +
    (colorSand  * fragWeights.b) +
    (colorMud   * fragWeights.a);

    float totalWeight = fragWeights.r + fragWeights.g + fragWeights.b + fragWeights.a;
    if (totalWeight > 0.0) {
        dynamicTerrainColor /= totalWeight;
    }

    outColor = dynamicTerrainColor;
}