java lwjgl 着色器错误

当我在关注 Thinmatrix 上的 java lwjgl 2.9 3D 游戏教程时。我遇到了烦人的问题（卡在 ep16:fog）：0(9) : error C0000: syntax error, unexpected reserved word "out", expecting ',' or ';' at token "out", Could not compile shader!

我检查了我的代码 2 次，仍然抛出异常，我不知道该怎么办了。

任何帮助是极大的赞赏。

编辑：如果您需要更多代码，请对其发表评论。

地形顶点着色器

#version 400 core

in vec3 position;
in vec2 textureCoordinates;
in vec3 normal;

out vec2 pass_textureCoordinates;
out vec3 surfaceNormal;
out vec3 toLightVector;
out vec3 toCameraVector;
out float visibility;

uniform mat4 transformationMatrix;
uniform mat4 projectionMatrix;
uniform mat4 viewMatrix;
uniform vec3 lightPosition;

const float density = 0.007;
const float gradient = 1.5;

void main(void){

    vec4 worldPosition = transformationMatrix * vec4(position,1.0);
    vec4 positionRelativeToCam = viewMatrix * worldPosition;
    gl_Position = projectionMatrix * positionRelativeToCam;
    pass_textureCoordinates = textureCoordinates * 40.0;

    surfaceNormal = (transformationMatrix * vec4(normal,0.0)).xyz;
    toLightVector = lightPosition - worldPosition.xyz;
    toCameraVector = (inverse(viewMatrix) * vec4(0.0,0.0,0.0,1.0)).xyz - 
    worldPosition.xyz;

    float distance = length(positionRelativeToCam.xyz);
    visibility = exp(-pow((distance*density), gradient));
    visibility = clamp(visibility, 0.0, 1.0);
}

陆地片段着色器

#version 400 core

in vec2 pass_textureCoordinates;
in vec3 surfaceNormal;
in vec3 toLightVector;
in vec3 toCameraVector;
in float visibility

out vec4 out_Color;

uniform sampler2D modelTexture;
uniform vec3 lightColour;
uniform float shineDamper;
uniform float reflectivity;
uniform vec3 skyColour;

void main(void){

    vec3 unitNormal = normalize(surfaceNormal);
    vec3 unitLightVector = normalize(toLightVector);

    float nDotl = dot(unitNormal,unitLightVector);
    float brightness = max(nDotl,0.0);
    vec3 diffuse = brightness * lightColour;

    vec3 unitVectorToCamera = normalize(toCameraVector);
    vec3 lightDirection = -unitLightVector;
    vec3 reflectedLightDirection = reflect(lightDirection,unitNormal);

    float specularFactor = dot(reflectedLightDirection , 
    unitVectorToCamera);
    specularFactor = max(specularFactor,0.0);
    float dampedFactor = pow(specularFactor,shineDamper);
    vec3 finalSpecular = dampedFactor * reflectivity * lightColour;


    out_Color =  vec4(diffuse,1.0) * textureColour + 
    vec4(finalSpecular,1.0);
    out_Color = mix(vec4(skyColour,1.0), out_Color, visibility);


}

陆地着色器

package shaders;

import org.lwjgl.util.vector.Matrix4f;
import org.lwjgl.util.vector.Vector3f;
import entities.Camera;
import entities.Light;
import toolbox.Maths;

public class TerrainShader extends ShaderProgram{


    private static final String VERTEX_FILE = 
    "src/shaders/terrainVertexShader.txt";
    private static final String FRAGMENT_FILE = 
    "src/shaders/terrainFragmentShader.txt";

    private int location_transformationMatrix;
    private int location_projectionMatrix;
    private int location_viewMatrix;
    private int location_lightPosition;
    private int location_lightColour;
    private int location_shineDamper;
    private int location_reflectivity;
    private int location_skyColour;

    public TerrainShader() {
        super(VERTEX_FILE, FRAGMENT_FILE);
    }

    @Override
    protected void bindAttributes() {
        super.bindAttribute(0, "position");
        super.bindAttribute(1, "textureCoordinates");
        super.bindAttribute(2, "normal");
    }

    @Override
    protected void getAllUniformLocations() {
        location_transformationMatrix = 
        super.getUniformLocation("transformationMatrix");
        location_projectionMatrix = 
        super.getUniformLocation("projectionMatrix");
        location_viewMatrix = super.getUniformLocation("viewMatrix");
        location_lightPosition = super.getUniformLocation("lightPosition");
        location_lightColour = super.getUniformLocation("lightColour");
        location_shineDamper = super.getUniformLocation("shineDamper");
        location_reflectivity = super.getUniformLocation("reflectivity");
        location_skyColour = super.getUniformLocation("skyColour");

    }

    public void loadSkyColour(float r, float g, float b) {
        super.loadVector(location_skyColour, new Vector3f(r,g,b));
    }

    public void loadShineVariables(float damper,float reflectivity){
        super.loadFloat(location_shineDamper, damper);
        super.loadFloat(location_reflectivity, reflectivity);
    }

    public void loadTransformationMatrix(Matrix4f matrix){
        super.loadMatrix(location_transformationMatrix, matrix);
    }

    public void loadLight(Light light){
        super.loadVector(location_lightPosition, light.getPosition());
        super.loadVector(location_lightColour, light.getColour());
    }

    public void loadViewMatrix(Camera camera){
        Matrix4f viewMatrix = Maths.createViewMatrix(camera);
        super.loadMatrix(location_viewMatrix, viewMatrix);
    }

    public void loadProjectionMatrix(Matrix4f projection){
        super.loadMatrix(location_projectionMatrix, projection);
    }
}