我在learnopengl.com上学习了骨骼动画教程,它运行得很好,动画效果也很好。但是,当3D模型移动(显示为黑色)时,光源不起作用,而在静止时,光源起作用。我可以假设问题出在普通人身上。如何计算动画模型的法线?
顶点着色器-ve3局部法线什么都不做,但我假设它有用途?
# version 330 core
layout(location = 0) in vec3 pos;
layout(location = 1) in vec3 norm;
layout(location = 2) in vec2 tex;
layout(location = 5) in ivec4 boneIds;
layout(location = 6) in vec4 weights;
uniform mat4 projection;
uniform mat4 view;
uniform mat4 model;
const int MAX_BONES = 100;
const int MAX_BONE_INFLUENCE = 4;
uniform mat4 finalBonesMatrices[MAX_BONES];
out vec2 TexCoords;
out vec3 FragPos;
out vec3 Normal;
void main()
{
vec4 totalPosition = vec4(0.0f);
for(int i = 0 ; i < MAX_BONE_INFLUENCE ; i++)
{
if(boneIds[i] == -1)
continue;
if(boneIds[i] >=MAX_BONES)
{
totalPosition = vec4(pos,1.0f);
break;
}
vec4 localPosition = (finalBonesMatrices[boneIds[i]] * weights[i]) * vec4(pos,1.0f);
totalPosition += localPosition;
vec3 localNormal =mat3(transpose(inverse(finalBonesMatrices[boneIds[i]]))) * norm;
}
mat4 viewModel = view * model;
gl_Position = projection * viewModel * totalPosition;
TexCoords = tex;
FragPos = pos;
Normal = norm;
}
片段着色器
# version 330 core
out vec4 FragColor;
struct Material {
sampler2D texture_diffuse1;
sampler2D texture_specular1;
float shininess;
};
struct DirLight {
vec3 direction;
vec3 ambient;
vec3 diffuse;
vec3 specular;
float intensityVal;
};
struct PointLight {
vec3 position;
float constant;
float linear;
float quadratic;
vec3 ambient;
vec3 diffuse;
vec3 specular;
float intensityVal;
};
struct SpotLight {
vec3 position;
vec3 direction;
float cutOff;
float outerCutOff;
float constant;
float linear;
float quadratic;
vec3 ambient;
vec3 diffuse;
vec3 specular;
float intensityVal;
};
# define MAX_POINT_LIGHTS 1
# define MAX_SPOT_LIGHTS 1
# define MAX_DIR_LIGHTS 1
in vec3 FragPos;
in vec3 Normal;
in vec2 TexCoords;
uniform vec3 viewPos;
uniform DirLight dirLight[MAX_DIR_LIGHTS];
uniform PointLight pointLights[MAX_POINT_LIGHTS];
uniform SpotLight spotLight[MAX_SPOT_LIGHTS];
uniform Material material;
// function prototypes
vec3 CalcDirLight(DirLight light, vec3 normal, vec3 viewDir);
vec3 CalcPointLight(PointLight light, vec3 normal, vec3 fragPos, vec3 viewDir);
vec3 CalcSpotLight(SpotLight light, vec3 normal, vec3 fragPos, vec3 viewDir);
void main()
{
// properties
vec3 norm = normalize(Normal);
vec3 viewDir = normalize(viewPos - FragPos);
vec3 result=vec3(0.0);
// directional lighting
for(int i = 0; i < MAX_DIR_LIGHTS; i++)
result += CalcDirLight(dirLight[i], norm, viewDir);
//point lights
for(int i = 0; i < MAX_POINT_LIGHTS; i++)
result += CalcPointLight(pointLights[i], norm, FragPos, viewDir);
// spot light
for(int i = 0; i < MAX_SPOT_LIGHTS; i++)
result += CalcSpotLight(spotLight[i], norm, FragPos, viewDir);
FragColor = vec4(result, 1.0);
}
// calculates the color when using a directional light.
vec3 CalcDirLight(DirLight light, vec3 normal, vec3 viewDir)
{
vec3 lightDir = normalize(-light.direction);
// diffuse shading
float diff = max(dot(normal, lightDir), 0.0);
// specular shading
vec3 reflectDir = reflect(-lightDir, normal);
float spec = pow(max(dot(viewDir, reflectDir), 0.0), material.shininess);
// combine results
vec3 ambient = light.ambient * vec3(texture(material.texture_diffuse1, TexCoords));
vec3 diffuse = light.diffuse * diff * vec3(texture(material.texture_diffuse1, TexCoords))*light.intensityVal;
vec3 specular = light.specular * spec * vec3(texture(material.texture_specular1, TexCoords))*light.intensityVal;
return (ambient + diffuse + specular);
}
// calculates the color when using a point light.
vec3 CalcPointLight(PointLight light, vec3 normal, vec3 fragPos, vec3 viewDir)
{
vec3 lightDir = normalize(light.position - fragPos);
// diffuse shading
float diff = max(dot(normal, lightDir), 0.0);
// specular shading
vec3 reflectDir = reflect(-lightDir, normal);
float spec = pow(max(dot(viewDir, reflectDir), 0.0), material.shininess);
// attenuation
float distance = length(light.position - fragPos);
float attenuation = 1.0 / (light.constant + light.linear * distance + light.quadratic * (distance * distance));
// combine results
vec3 ambient = light.ambient * vec3(texture(material.texture_diffuse1, TexCoords));
vec3 diffuse = light.diffuse * diff * vec3(texture(material.texture_diffuse1, TexCoords))*light.intensityVal;
vec3 specular = light.specular * spec * vec3(texture(material.texture_specular1, TexCoords))*light.intensityVal;
ambient *= attenuation;
diffuse *= attenuation;
specular *= attenuation;
return (ambient + diffuse + specular);
}
// calculates the color when using a spot light.
vec3 CalcSpotLight(SpotLight light, vec3 normal, vec3 fragPos, vec3 viewDir)
{
vec3 lightDir = normalize(light.position - fragPos);
// diffuse shading
float diff = max(dot(normal, lightDir), 0.0);
// specular shading
vec3 reflectDir = reflect(-lightDir, normal);
float spec = pow(max(dot(viewDir, reflectDir), 0.0), material.shininess);
// attenuation
float distance = length(light.position - fragPos);
float attenuation = 1.0 / (light.constant + light.linear * distance + light.quadratic * (distance * distance));
// spotlight intensity
float theta = dot(lightDir, normalize(-light.direction));
float epsilon = light.cutOff - light.outerCutOff;
float intensity = clamp((theta - light.outerCutOff) / epsilon, 0.0, 1.0);
// combine results
vec3 ambient = light.ambient * vec3(texture(material.texture_diffuse1, TexCoords));
vec3 diffuse = light.diffuse * diff * vec3(texture(material.texture_diffuse1, TexCoords))*light.intensityVal;
vec3 specular = light.specular * spec * vec3(texture(material.texture_specular1, TexCoords))*light.intensityVal;
ambient *= attenuation * intensity;
diffuse *= attenuation * intensity;
specular *= attenuation * intensity;
return (ambient + diffuse + specular);
}
如何将正确的法线传递给片段着色器?
1条答案
按热度按时间yzckvree1#
如何计算动画模型的法线?
就像处理位置一样,需要计算变换的法线的加权平均值。
顶点着色器-ve3局部法线什么都不做,但我假设它有用途?
没错。此代码看起来未完成。
localNormal
为第i次骨转换后的输入法线。剩下的就是取平均值,并将*传递给片段着色器: