Unity3d Shaderlab using Blinnphong high light type

Unity3d Shaderlab using blinnphong high Light type

In the previous article we implemented a custom highlight type, this one, we say Blinn High Light, which is another way to calculate and estimate the high light, which is done by the half-width vector formed by the line of sight and the direction of light.

This is more efficient than forming a reflection vector for our own calculation. the Blinnphong illumination model built into the unitycg.cginc file is the half-width vector.

First, create a shader, a material ball, double-click shader, and open the editor.

1:Properties

Properties {

_maintex ("Base (RGB)", 2D) = "White" {}

_maintint ("Diffuse Tint", Color) = (1,1,1,1)

_specularcolor ("Specular color", color) = (1,1,1,1)

_specularpower ("Specular Power", Range (0.1,30)) =1

}

2:subshader declaration variable

Cgprogram

#pragma surface surf Myblinnphong

Sampler2d _maintex;

FLOAT4 _specularcolor;

FLOAT4 _maintint;

float _specularpower;

3:lightingmyblinnphong Illumination Model implementation

Inline fixed4 lightingmyblinnphong (surfaceoutput s,fixed3 lightdir,half3 viewdir, fixed atten) {

FLOAT3 Halfvector = normalize (Lightdir+viewdir);

float diff = max (0,dot (S.normal, Lightdir));

Float NH = max (0,dot (S.normal, halfvector));

FLOAT spec = POW (nh,_specularpower) *_specularcolor;

FLOAT4 C;

C.rgb = (S.albedo*_lightcolor0.rgb*diff) + (_lightcolor0.rgb*_specularcolor.rgb*spec) * (atten*2);

C.A = S.alpha;

return C;

}

4:surf function

Half4 C = tex2d (_maintex, In.uv_maintex) *_maintint;

The final effect is as follows:

The leftmost is the Blinnphong, the rightmost is the custom Phong, the middle is the most basic highlight effect.

The Blinnphong high-light model and the Phong High-gloss model are almost identical, except that the former uses less code more efficiently, and their effect is almost identical.

In the Lightingmyblinnphong illumination model above, we obtained the half-width vector by normalize in order to obtain the half-angle vector, the line of sight direction and the incident direction superposition .

we then simply multiply the vertex normals and the new half-width vectors to obtain our high-light values and thenSpecularpowermultiply the highlight color value after the power of the second partySpecularcolor

Although the process is simplified, it also gives us excellent high-gloss effects.

Code Start--------------------------------------------------------------------------------

Shader "91ygame/blinnphong" {
Properties {
_maintex ("Base (RGB)", 2D) = "White" {}
_maintint ("Diffuse Tint", Color) = (1,1,1,1)
_specularcolor ("Specular color", color) = (1,1,1,1)
_specularpower ("Specular Power", Range (0.1,30)) =1
}
Subshader {
Tags {"Rendertype" = "Opaque"}
LOD 200

Cgprogram
#pragma surface surf Myblinnphong

Sampler2d _maintex;
FLOAT4 _specularcolor;
FLOAT4 _maintint;
float _specularpower;

struct Input {
FLOAT2 Uv_maintex;
};

Inline fixed4 lightingmyblinnphong (surfaceoutput s,fixed3 lightdir,half3 viewdir, fixed atten) {
FLOAT3 Halfvector = normalize (Lightdir+viewdir);
float diff = max (0,dot (S.normal, Lightdir));
Float NH = max (0,dot (S.normal, halfvector));
FLOAT spec = POW (nh,_specularpower) *_specularcolor;

FLOAT4 C;
C.rgb = (S.albedo*_lightcolor0.rgb*diff) + (_lightcolor0.rgb*_specularcolor.rgb*spec) * (atten*2);
C.A = S.alpha;
return C;
}

void Surf (Input in, InOut surfaceoutput o) {
Half4 C = tex2d (_maintex, In.uv_maintex) *_maintint;
O.albedo = C.rgb;
O.alpha = C.A;
}
Endcg
}
FallBack "Diffuse"
}

Code End--------------------------------------------------------------------------------

Unity3d Shaderlab using Blinnphong high light type