GLSL中的语法错误 - 意外的NEW_IDENTIFIER

Question

我一直在编写一种用于简化GLSL编写的着色语言。因此，我不能真正依赖GLSL编译器给出的行号。因此，我找不到这个错误试图说的内容。首先是什么意思，然后我该如何解决？

错误代码：

0:8(18): error: syntax error, unexpected NEW_IDENTIFIER, expecting '{'

我认为这只是意味着生成的GLSL存在语法错误，但我找不到。这个错误信息实际意味着什么？

- 编辑 -

很抱歉没有提供代码，我想知道错误的含义，因此我可以提供相关的代码区域。

生成的顶点着色器：

#version 120

attribute vec3 position;
attribute vec2 texCoord;
attribute vec3 normal;
attribute vec3 tangent;

varying vec2 fragTexCoords;
varying vec3 worldPos;
varying vec4 shadowMapCoords;
varying mat3 tbnMatrix;

uniform mat4 modelMatrix;
uniform mat4 MVPMatrix;
uniform mat4 lightMatrix;

void main() {
    gl_Position = MVPMatrix * vec4(position, 1);
    fragTexCoords = texCoord;
    shadowMapCoords = lightMatrix * vec4(position, 1);
    worldPos = (modelMatrix * vec4(position, 1)).xyz;

    vec3 n = normalize((modelMatrix * vec4(normal, 0)).xyz);
    vec3 t = normalize((modelMatrix * vec4(tangent, 0)).xyz);
    t = normalize(t - dot(t, n) * n);

    vec3 biTangent = cross(t, n);
    tbnMatrix = mat3(t, biTangent, n);
}

生成的片段着色器：

#version 120

varying vec2 fragTexCoords;
varying vec3 worldPos;
varying vec4 shadowMapCoords;
varying mat3 tbnMatrix;

uniform Material material;
uniform Light light;
uniform vec3 eyePos;

uniform sampler2D shadowMap;
uniform float shadowVarianceMin;
uniform float shadowLightBleedReduction;

bool inRange(float value) {
    return value >= 0 && value <= 1;
}

float linStep(float low, float high, float v) {
    return clamp((v - low) / (high - low), 0, 1);
}

vec2 calcParallaxTexCoords(sampler2D dispMap, mat3 tbnMatrix, vec3 directionToEye, vec2 texCoords, float scale, float bias) {
    return texCoords.xy + (directionToEye * tbnMatrix).xy * (texture2D(dispMap, texCoords.xy).r * scale + bias);
}

float sampleShadowMap(sampler2D shadowMap, vec2 coords, float compare) {
    return step(compare, texture2D(shadowMap, coords.xy).r);
}

float sampleVarianceShadowMap(sampler2D shadowMap, vec2 coords, float compare, float varianceMin, float lightBleedReduction) {
    vec2 moments = texture2D(shadowMap, coords.xy).xy;

    float p = step(compare, moments.x);
    float variance = max(moments.y - moments.x * moments.x, varianceMin);

    float d = compare - moments.x;
    float pMax = linStep(lightBleedReduction, 1, variance / (variance + d * d));

    return min(max(p, pMax), 1);
}

struct Light {
    vec3 color;
    float intensity;
    vec3 direction;
};

struct Material {
    float roughness;
    float fresnelReflectance;

    sampler2D diffuseTexture;
    sampler2D normalMap;
    sampler2D dispMap;

    float dispMapScale;
    float dispMapBias;
};

vec3 calcLight(Light light, Material material, vec3 surfaceNormal, vec3 eyePos, vec3 diffuseColor, vec3 specularColor) {
    vec3 halfVector     = normalize(light.direction + eyePos);
    float NdotL         = clamp(dot(surfaceNormal, light.direction),    0.0, 1.0);
    float NdotH         = clamp(dot(surfaceNormal, halfVector),         0.0, 1.0);
    float NdotV         = clamp(dot(surfaceNormal, eyePos),             0.0, 1.0);
    float VdotH         = clamp(dot(eyePos, halfVector),                0.0, 1.0);
    float rSq           = material.roughness * material.roughness;

    // ----- Fresnel term -----
    float fresnel = pow(1 - VdotH, 5.0);
    fresnel *= 1 - material.fresnelReflectance;
    fresnel += material.fresnelReflectance;

    // ----- Geometric attenuation term -----
    float geoNum = 2.0 * NdotV;
    float geoB   = (geoNum * NdotV) / VdotH;
    float geoC   = (geoNum * NdotL) / VdotH;
    float geo    = min(1.0, min(geoB, geoC));

    // ----- Roughness term -----
    float roughnessA = rSq * pow(NdotH, 4.0);
    float roughnessB = (NdotH * NdotH - 1.0) / (rSq * NdotH * NdotH);
    float roughness = 1.0 / roughnessA * exp(roughnessB);

    // ----- Cook-Torrance calculation -----
    vec3 specular = vec3(fresnel * roughness * geo) / (NdotV * NdotL);

    return max(0.0, NdotL) * (specularColor * specular + diffuseColor);
}

float calcShadowAmount(sampler2D shadowMap, vec4 initialShadowMapCoords) {
    vec3 shadowMapCoords = (initialShadowMapCoords.xyz / initialShadowMapCoords.w);

    if (inRange(shadowMapCoords.x) && inRange(shadowMapCoords.y) && inRange(shadowMapCoords.z)) {
        return sampleVarianceShadowMap(shadowMap, shadowMapCoords.xy, shadowMapCoords.z, shadowVarianceMin, shadowLightBleedReduction);
    } else {
        return 1.0;
    }
}

float calcBasicShadowAmount(sampler2D shadowMap, vec4 initialShadowMapCoords) {
    vec3 shadowMapCoords = (initialShadowMapCoords.xyz / initialShadowMapCoords.w);

    return sampleShadowMap(shadowMap, shadowMapCoords.xy, shadowMapCoords.z);
}

void main() {
    vec3 directionToEye = normalize(eyePos - worldPos);
    vec2 texCoords = calcParallaxTexCoords(dispMap, tbnMatrix, directionToEye, fragTexCoords, dispMapScale, dispMapBias);
    vec3 normal = normalize(tbnMatrix * (255.0 / 128.0 * texture2D(normalMap, texCoords).xyz - 1));

    gl_FragColor = calcLight(light, material, normal, eyePos, texture2D(diffuse, texCoords), vec3(1, 1, 1));
}

Answer 1

GLSL错误报告约定是特定于供应商的，因此难以解析。但是，在这种情况下，0:8(18): error: syntax error, unexpected NEW_IDENTIFIER, expecting '{'引用 8 行，字符 18 。

如果您查看片段着色器，请在 8 一行中显示以下内容：

uniform Material material;
                 ^ char. 18

这里的问题是你还没有定义Material的结构。

您需要将这些structs移到uniforms之前：

struct Light {
    vec3 color;
    float intensity;
    vec3 direction;
};

struct Material {
    float roughness;
    float fresnelReflectance;

    sampler2D diffuseTexture;
    sampler2D normalMap;
    sampler2D dispMap;

    float dispMapScale;
    float dispMapBias;
};