可以感知与其他对象交叉的着色器

时间:2016-12-22 05:52:53

标签: unity3d shader cg

我是一个初学者着色器世界,它很难学习(无论如何我在某个时候尝试)。我正在寻找一个可以感知与其他物体碰撞/交叉的着色器,这样我就可以在那个交叉点停止渲染。我目前得到这个着色器,它允许检测交叉点(不知道如何),但它的网格渲染不会停止。

Shader "Custom/IntersectionHighlights"
{
    Properties
    {
        _RegularColor("Main Color", Color) = (1, 1, 1, .5) //Color when not intersecting
        _HighlightColor("Highlight Color", Color) = (1, 1, 1, .5) //Color when intersecting
        _HighlightThresholdMax("Highlight Threshold Max", Float) = 1 //Max difference for intersections
    }
    SubShader
    {
        Tags { "Queue" = "Transparent" "RenderType"="Transparent"  }
        Pass
        {
            Blend SrcAlpha OneMinusSrcAlpha
            ZWrite Off
            Cull Off

            CGPROGRAM
            #pragma target 3.0
            #pragma vertex vert
            #pragma fragment frag
            #include "UnityCG.cginc"

            uniform sampler2D _CameraDepthTexture; //Depth Texture
            uniform float4 _RegularColor;
            uniform float4 _HighlightColor;
            uniform float _HighlightThresholdMax;

            struct v2f
            {
                float4 pos : SV_POSITION;
                float4 projPos : TEXCOORD1; //Screen position of pos
            };

            v2f vert(appdata_base v)
            {
                v2f o;
                o.pos = mul(UNITY_MATRIX_MVP, v.vertex);
                o.projPos = ComputeScreenPos(o.pos);

                return o;
            }

            half4 frag(v2f i) : COLOR
            {
                float4 finalColor = _RegularColor;

                //Get the distance to the camera from the depth buffer for this point
                float sceneZ = LinearEyeDepth (tex2Dproj(_CameraDepthTexture,
                                                         UNITY_PROJ_COORD(i.projPos)).r);

                //Actual distance to the camera
                float partZ = i.projPos.z;

                //If the two are similar, then there is an object intersecting with our object
                float diff = (abs(sceneZ - partZ)) /
                    _HighlightThresholdMax;

                if(diff <= 1)
                {
                    finalColor = lerp(_HighlightColor,
                                      _RegularColor,
                                      float4(diff, diff, diff, diff));
                }

                half4 c;
                c.r = finalColor.r;
                c.g = finalColor.g;
                c.b = finalColor.b;
                c.a = finalColor.a;

                return c;
            }

            ENDCG
        }
    }
    FallBack "VertexLit"
}

0 个答案:

没有答案