#Intensity light reflection equation full
#Intensity light reflection equation free

The input vectors are automatically set to the POSITION, NORMAL and first textureĬoordinate ( TEXCOORD0) of the vertex by DirectX (which in turn receives it from theĮngine, see chapter: 'D3D Pipeline') because they are marked with the corresponding input We define the function DiffuseVS which takes three input vectors and also returns three vectors. Pass the texture coordinate to the pixel shader: OutNormal = normalize(mul(InNormal, matWorld)) Transform the normal from object space to world space: Transform the vertex from object space to clip space: The ambient lighting shader: // Vertex Shader: The vertex shader for our diffuse lighting tutorial is only slightly more complex than that of

#Intensity light reflection equation full

For a full list of sampler_state settings,Ĭheck MSDN (see Further Reading section of this tutorial).

We also specify a linear mipmap filter - by default, sampers don't support mipmapping. We could also omit the AddressU/AddressV lines or choose to Wrap the coordinates (which is the default) for repeating textures. Outside the texture size, they are Clamped - the last pixel of the texture is returned. A sampler is an object that defines how a texture should be read.Īll we specify for this sampler, called ColorMapSampler is that if the texture coordinates are This shader will expect that the color texture is stored in entSkin1 that was set up in MED. The texture is also sent from the engine and thus must be namedĪccording to the list of effect variables from the manual: entSkin1 for the first model skin. We have also added a new vector that will be set to the sun light direction by the engine. Next we define a second matrix for transforming the vertex normal from object space to world

#Intensity light reflection equation free

Intensity and the other is the color of the sunlight (feel free to experiment with different MipFilter = Linear // required for mipmappingĪs you can see, two new variables have been added under tweakables. Texture entSkin1 // Model texture // Color map sampler Application fed data:Ĭonst float4x4 matWorldViewProj // World*view*projection matrix.Ĭonst float4x4 matWorld // World matrix.Ĭonst float4 vecAmbient // Ambient color, passed by the engine.Ĭonst float4 vecSunDir // The sun light direction vector. Static const float4 SunColor = // Color vector of the sunlight.

Static const float DiffuseIntensity = 1.0f // The intensity of the diffuse light. Static const float AmbientIntensity = 1.0f // The intensity of the ambient light. The diffuse color will be read from the texture map. The diffuse equation is:įinal Color = (Diffuse Light + Ambient Light) * Diffuse Color The dot product equals cos(α) if N and L are unit vectors. If we use normalized vectors we can simplify this to: We don't know the angle between N and L, but we can use theįollowing property of the dot product to calculate it: If we take the cosine of the angle between N and L we get 1 when they are aligned and 0 Perpendicular, no diffuse light is reflected. When N and L are aligned (in other words: when the lightīeam is perpendicular to the surface) the reflection is at its peak, when N and L are The amount of light that is reflected is directly proportional to the angle between the lightĭirection and the surface normal. From now on, L is the light direction vector and N is the surface normal: This makes it suitable for simulating matteĭiffuse light is emitted by dynamic light sources and by the sun. Lighting is not dependent on the view position. Because the light is reflected equally into all directions the diffuse Surface orientation into account to calculate the amount of light that is reflected from the The diffuse lighting model will take the light direction and the To overcome some of the limitations of the ambient lighting model we will now add a diffuse Shader Workshops Workshop 2 - Diffuse Lighting