问题描述
我正在尝试在我的OpenTK渲染场景中实现照明。奇怪的是，由于我在着色器和代码中实施了漫射照明，因此所有对象纹理仅在对象的INSIDES中可见。或者只是看起来像这样。
您能帮我吗？我希望这只是一个简单的虚拟问题。
您可以在此处找到完整的代码：https://github.com/BanditBloodwyn/TerritorySimulator。
重要文件是：
- Rendering.Core.Rendering.Renderer.cs
- Rendering.Core.Classes.Shapes.GLSphere.cs
- Rendering.Core.Classes.Shaders.GLSL.Fragment
这是着色器：
#version 420 core
in vec3 normal;
in vec2 texCoord;
in vec3 FragPos;
out vec4 FragColor;
uniform sampler2D texture0;
uniform sampler2D texture1;
struct Material {
sampler2D diffuse;
sampler2D specular;
float shininess;
};
struct Light {
vec3 position;
vec3 ambient;
vec3 diffuse;
vec3 specular;
};
uniform Material material;
uniform Light light;
void main()
{
// Ambient
vec3 ambient = light.ambient * vec3(texture(material.diffuse,texCoord));
// Diffuse
vec3 norm = normalize(normal);
vec3 lightDir = normalize(vec3(light.position - FragPos));
float diff = max(dot(norm,lightDir),0.0);
vec3 diffuse = light.diffuse * diff * vec3(texture(material.diffuse,texCoord));
vec3 result = ambient + diffuse;
//if(result.a < 0.1)
// discard;
FragColor = vec4(result,1.0);
}
这是渲染功能：
public void Render()
{
GL.Clear(ClearBufferMask.ColorBufferBit | ClearBufferMask.DepthBufferBit);
if (Shapes == null || Shapes.Length == 0)
return;
IntPtr offset = (IntPtr)0;
foreach (GLShape shape in Shapes)
{
ApplyTextures(shape);
ApplyModelTransforms(shape,out Matrix4 model);
objectShader.SetMatrix4("model",model);
GL.DrawElements(PrimitiveType.Triangles,shape.Indices.Length,DrawElementsType.UnsignedInt,offset);
offset += shape.IndexBufferSize;
}
objectShader.SetVector3("material.ambient",new Vector3(1.0f,0.5f,0.31f));
objectShader.SetVector3("material.diffuse",0.31f));
objectShader.SetVector3("material.specular",new Vector3(0.5f,0.5f));
objectShader.SetVector3("light.position",new Vector3(100f,1.0f,2.0f));
objectShader.SetVector3("light.ambient",new Vector3(1.0f));
objectShader.SetVector3("light.diffuse",new Vector3(0.5f));
objectShader.SetVector3("light.specular",new Vector3(1.0f));
objectShader.SetMatrix4("view",Camera.GetViewMatrix());
objectShader.SetMatrix4("projection",Camera.GetProjectionMatrix());
objectShader.Use();
}
更清楚地说：根据我的理解，我将光源在世界空间中的位置设置为{100，1，2}。由于世界球体的半径为20，因此光源应位于其外部，因此应从外部进行照明。 资料的所有参数均来自OpenTK教程，该教程向我展示了OpenGL和OpenTK的基础知识，因此，我希望它们是正确的，或者至少不是造成我问题的原因。 除了环境强度（我将其设置为1.0以“禁用”环境照明的调光效果）外，光源参数与同一教程相似。 “形状”是包含世界上所有对象的数组。
在此处设置了着色器：
private void SetupObjectShader()
{
string vertexPath = Path.Combine(Environment.CurrentDirectory,@"GLSL\","Vertex.vert");
string fragmentPath = Path.Combine(Environment.CurrentDirectory,"Fragment.frag");
objectShader = new Shader(vertexPath,fragmentPath);
objectShader.Use();
int vertexLocation = objectShader.GetAttribLocation("aPosition");
GL.EnabLevertexAttribArray(vertexLocation);
GL.VertexAttribPointer(
vertexLocation,3,VertexAttribPointerType.Float,false,8 * sizeof(float),0);
int normCoordLocation = objectShader.GetAttribLocation("anormal");
GL.EnabLevertexAttribArray(normCoordLocation);
GL.VertexAttribPointer(
normCoordLocation,3 * sizeof(float));
int texCoordLocation = objectShader.GetAttribLocation("aTexCoord");
GL.EnabLevertexAttribArray(texCoordLocation);
GL.VertexAttribPointer(
texCoordLocation,2,6 * sizeof(float));
objectShader.SetInt("texture0",0);
objectShader.SetInt("texture1",1);
}
在下一个函数中，VertexAttribPointer函数的步幅和偏移值将变得很清楚，在这里您可以看到顶点的构建方式：3个用于位置的浮动，3个用于法线的浮动，2个纹理坐标。
这样创建对象（在我的情况下是所有球体）。请查看如何创建顶点和法线：
private void RecreateVertices()
{
List<float> vertices = new List<float>();
float alpha = 2 * (float)Math.PI / rasterization;
for (int i = 0; i < rasterization + 1; i++)
{
for (int j = 0; j < rasterization + 1; j++)
{
float x = radius * (float)Math.Sin(i * alpha * 1.0) * (float)Math.Sin(j * alpha);
float y = radius * (float)Math.Sin(i * alpha * 1.0) * (float)Math.Cos(j * alpha);
float z = radius * (float)Math.Cos(i * alpha * 1.0);
float textureX = (float)j / rasterization;
float textureY = (float)i / rasterization * 2;
Vector3 normal = Createnormal(x,y,z);
vertices.AddRange(new[] { x,z,normal[0],normal[1],normal[2],textureX,textureY });
}
}
Vertices = vertices.ToArray();
}
private Vector3 Createnormal(float x,float y,float z)
{
Vector3 normVector3 = new Vector3(x,z);
normVector3.normalize();
return normVector3;
}
更新： 我使用片段着色器进行了一些实验。 我尝试使用白色光和橙色作为对象，而不是使用纹理。我得到的是静态橙色图像，而不是可见的照明对象。也许这有助于诊断。
#version 420 core
in vec3 normal;
in vec2 texCoord;
in vec3 FragPos;
out vec4 FragColor;
uniform sampler2D texture0;
uniform sampler2D texture1;
struct Material {
sampler2D diffuse;
sampler2D specular;
float shininess;
};
struct Light {
vec3 position;
vec3 ambient;
vec3 diffuse;
vec3 specular;
};
uniform Material material;
uniform Light light;
uniform vec3 viewPos;
void main()
{
// Ambient
// vec3 ambient = light.ambient * vec3(texture(material.diffuse,texCoord));
vec3 ambient = light.ambient * vec3(1.0f,1.0f);
// Diffuse
vec3 norm = normalize(normal);
vec3 lightDir = normalize(vec3(light.position - FragPos));
float diff = max(dot(norm,0.0);
//vec3 diffuse = light.diffuse * diff * vec3(texture(material.diffuse,texCoord));
vec3 diffuse = light.diffuse * diff * vec3(1.0f,1.0f);
// specular
vec3 viewDir = normalize(viewPos - FragPos);
vec3 reflectDir = reflect(-lightDir,norm);
float spec = pow(max(dot(viewDir,reflectDir),0.0),material.shininess);
// vec3 specular = light.specular * spec * vec3(texture(material.specular,texCoord));
vec3 specular = light.specular * spec * vec3(1.0f,1.0f);
vec3 result = (ambient + diffuse + specular) * vec3(1.0f,0.31f);
//if(result.a < 0.1)
// discard;
FragColor = vec4(result,1.0);
}
解决方法
在设置制服之前，着色器程序需要与GL.UseProgram一起安装。 GL.Uniform *在当前安装的程序的默认统一块中设置统一值：
objectShader.Use();
objectShader.SetVector3("material.ambient",new Vector3(1.0f,0.5f,0.31f));
objectShader.SetVector3("material.diffuse",0.31f));
objectShader.SetVector3("material.specular",new Vector3(0.5f,0.5f));
objectShader.SetVector3("light.position",new Vector3(100f,1.0f,2.0f));
objectShader.SetVector3("light.ambient",new Vector3(1.0f));
objectShader.SetVector3("light.diffuse",new Vector3(0.5f));
objectShader.SetVector3("light.specular",new Vector3(1.0f));
objectShader.SetMatrix4("view",Camera.GetViewMatrix());
objectShader.SetMatrix4("projection",Camera.GetProjectionMatrix());
我发现了一个问题。顶点着色器配置不正确。我更新了它，如下所示。现在的结果是，最终我可以看到漫反射和镜面反射的灯光效果，但仍然只在球体的内部。
您可以看到漫反射和镜面反射光起作用（我将环境光设置为0.0，以便可以更好地看到其他光分量）。 由于世界球的半径为20.0f ，因此灯光位置设置为 x：1000.0f，y：1.0f，z：0.0f 。我希望光线在外面（当然是我想要的），并且远离它。
该如何解决“外部问题”？法线错误？错误或否定否定在任何地方？
这里是“新”顶点着色器：
#version 420 core
layout (location = 0) in vec3 aPosition;
layout (location = 1) in vec3 aNormal;
layout (location = 2) in vec2 aTexCoord;
out vec2 texCoord;
out vec3 FragPos;
out vec3 Normal;
uniform mat4 model;
uniform mat4 view;
uniform mat4 projection;
void main(void)
{
texCoord = aTexCoord;
FragPos = vec3(vec4(aPosition,1.0) * model);
Normal = -aNormal * mat3(transpose(inverse(model)));
gl_Position = vec4(aPosition,1.0) * model * view * projection;
}
这是片段着色器的当前状态：
#version 420 core
in vec3 FragPos;
in vec3 Normal;
in vec2 texCoord;
out vec4 FragColor;
uniform sampler2D texture0;
uniform sampler2D texture1;
struct Material {
sampler2D diffuse;
sampler2D specular;
float shininess;
};
struct Light {
vec3 position;
vec3 ambient;
vec3 diffuse;
vec3 specular;
};
uniform Material material;
uniform Light light;
uniform vec3 viewPos;
void main()
{
// Ambient
vec3 ambient = light.ambient * vec3(texture(material.diffuse,texCoord));
// Diffuse
vec3 norm = normalize(Normal);
vec3 lightDir = normalize(vec3(light.position - FragPos));
float diff = max(dot(norm,lightDir),0.0);
vec3 diffuse = light.diffuse * diff * vec3(texture(material.diffuse,texCoord));
// Specular
vec3 viewDir = normalize(viewPos - FragPos);
vec3 reflectDir = reflect(-lightDir,norm);
float spec = pow(max(dot(viewDir,reflectDir),0.0),material.shininess);
vec3 specular = light.specular * spec * vec3(texture(material.specular,texCoord));
vec3 result = ambient + diffuse + specular;
FragColor = vec4(result,1.0);
}
我发现了问题。我忘了提及地球球体上方的另一个具有透明纹理的球体。在新的light实施中，alpha混合不起作用。
我将其提出了一个新问题。谢谢Rabbid76的参与！