Topics to cover

• Initialize D3D11 context

• Process input and camera control

• Load simple model without animation (teapot, statue, car, plane, tank etc.)

• Load mip-mapped textures (diffuse, normal, specular, gloss)

• Calculate Phong lighting from direct and point lights in the pixel shader

• Particle System (10000+ particles)

• Make soft shadows (SM+PCF, VSM or ESM)

• Make dynamic environment reflections via render to cube map

• Add fog effect (pixel shader or post-process)

• Add bloom post-process effect

Notes

Lighting

In local illumination model we calculate lighting for an object as if there is no other objects. Thus light ray from light source does not bounces from any objects except the one we calculate lighting for.

Calculating Phong lighting

Calculating Diffuse lighting

We assume that light scatters equally in all directions above the surface. Thus we can ignore the eye position.

We calculate diffuse lighting by first multiplying component wise diffuse light color and diffuce material color:

D = l_d ⊗ m_d;

Example:

D = l_d ⊗ m_d = (0.8,0.8,0.8) ⊗ (0.5,1.0,0.75) = (0.4,0.8,0.6)

Here ⊗ denotes component wise vector multiplication.

After that we include Lambert's cosine law:

f(θ) = max(cos θ, 0) = max (L * n, 0)

where L is a unit vector in direction of light vector (light vector is the vector from the surface to the light source) and n is the normal vector.

Let l_d be the diffuse light color, m_d be the diffuse material color, and k_d = f(θ). Then the amout of diffuse light reflected off a point is given by:

c_d = k_d * l_d ⊗ m_d = k_d * D

Calculating the Ambient lighting

Ambient lighting is an emulation of light bouncing from other objects. Let l_a be the ambient light color, m_a be the ambient material color, then the amount of ambient light reflected off a point is given by:

A = l_a ⊗ m_a

Calculating the Specular lighting

c_s = k_s * l_s ⊗ m_s = k_s * S

where l_s is the specular light color, m_s is the specular material component, and

k_s = max (v*r, 0)^p, when L * n > 0, or k_s = 0, when L * n <= 0.

Here L is the unit light vector, n is the normal, k_s - coeficient that depends on exponent p. The more the p is the more sharply the light reflects of the surface. v is a reflected ray of light.

v is the unit vector that is given by

v = E - P / || E - P ||,

where E is the position of eye and P is the surface point.

Phong lighting formula

LitColor = l_a ⊗ m_a + k_d * l_d ⊗ m_d + k_s * l_s ⊗ m_s = A + k_d * D + k_s * S

Lighting with attenuation:

LitColor = A + (k_d * D + k_s * S) / (a_0 + a1 * d + a2 * d^2)

where d is a distance from light source. We can calculate distance as length of vector V = Q - P, where Q is the position of light source, and P is the point on the surface that is lit by light source.