Add Open Brush startup logo (#214)

* Add Open Brush startup logo

* Make logo fully transparent before appearing

Assets/Materials/IntroMaterials/Intro_Logo.mat

@@ -0,0 +1,87 @@
+%YAML 1.1
+%TAG !u! tag:unity3d.com,2011:
+--- !u!21 &2100000
+Material:
+  serializedVersion: 6
+  m_ObjectHideFlags: 0
+  m_CorrespondingSourceObject: {fileID: 0}
+  m_PrefabInstance: {fileID: 0}
+  m_PrefabAsset: {fileID: 0}
+  m_Name: Intro_Logo
+  m_Shader: {fileID: 4800000, guid: 1c5f7863e38446344b9db133ad17843e, type: 3}
+  m_ShaderKeywords: _ALPHATEST_ON _LIGHTMAPPING_DYNAMIC_LIGHTMAPS _UVSEC_UV1
+  m_LightmapFlags: 5
+  m_EnableInstancingVariants: 0
+  m_DoubleSidedGI: 0
+  m_CustomRenderQueue: -1
+  stringTagMap: {}
+  disabledShaderPasses: []
+  m_SavedProperties:
+    serializedVersion: 3
+    m_TexEnvs:
+    - _BumpMap:
+        m_Texture: {fileID: 0}
+        m_Scale: {x: 1, y: 1}
+        m_Offset: {x: 0, y: 0}
+    - _DetailAlbedoMap:
+        m_Texture: {fileID: 0}
+        m_Scale: {x: 1, y: 1}
+        m_Offset: {x: 0, y: 0}
+    - _DetailMask:
+        m_Texture: {fileID: 0}
+        m_Scale: {x: 1, y: 1}
+        m_Offset: {x: 0, y: 0}
+    - _DetailNormalMap:
+        m_Texture: {fileID: 0}
+        m_Scale: {x: 1, y: 1}
+        m_Offset: {x: 0, y: 0}
+    - _EmissionMap:
+        m_Texture: {fileID: 0}
+        m_Scale: {x: 1, y: 1}
+        m_Offset: {x: 0, y: 0}
+    - _MainTex:
+        m_Texture: {fileID: 2800000, guid: 819e7471e6f639f4da51f3b379351b19, type: 3}
+        m_Scale: {x: 1, y: 1}
+        m_Offset: {x: 0, y: 0}
+    - _Occlusion:
+        m_Texture: {fileID: 0}
+        m_Scale: {x: 1, y: 1}
+        m_Offset: {x: 0, y: 0}
+    - _OcclusionMap:
+        m_Texture: {fileID: 0}
+        m_Scale: {x: 1, y: 1}
+        m_Offset: {x: 0, y: 0}
+    - _ParallaxMap:
+        m_Texture: {fileID: 0}
+        m_Scale: {x: 1, y: 1}
+        m_Offset: {x: 0, y: 0}
+    - _SpecGlossMap:
+        m_Texture: {fileID: 0}
+        m_Scale: {x: 1, y: 1}
+        m_Offset: {x: 0, y: 0}
+    m_Floats:
+    - _AlphaTestRef: 0.5
+    - _Aspect: 1
+    - _BumpScale: 1
+    - _Cutoff: 0.5
+    - _DetailNormalMapScale: 1
+    - _DstBlend: 0
+    - _EmissionScaleUI: 1
+    - _Glossiness: 0
+    - _Grayscale: 0
+    - _IntroDissolve: 1
+    - _Lightmapping: 1
+    - _Mode: 1
+    - _OcclusionStrength: 1
+    - _Parallax: 0.02
+    - _Progress: 0
+    - _SrcBlend: 1
+    - _UVSec: 0
+    - _ZWrite: 1
+    m_Colors:
+    - _Color: {r: 1, g: 1, b: 1, a: 1}
+    - _EmissionColor: {r: 0, g: 0, b: 0, a: 0.99999994}
+    - _EmissionColorUI: {r: 0, g: 0, b: 0, a: 1}
+    - _EmissionColorWithMapUI: {r: 1, g: 1, b: 1, a: 1}
+    - _SpecColor: {r: 0.2, g: 0.2, b: 0.2, a: 1}
+    - _SpecularColor: {r: 0.2, g: 0.2, b: 0.2, a: 1}

Assets/Materials/IntroMaterials/Shaders/Intro_LogoImage.shader

@@ -0,0 +1,139 @@
+// Copyright 2020 The Tilt Brush Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+Shader "Custom/Intro_Image" {
+  Properties {
+    _IntroDissolve ("Progress", Float) = 0
+    _Color ("Main Color", Color) = (1,1,1,1)
+    _MainTex ("Texture", 2D) = "white" {}
+  }
+  SubShader {
+    Tags { "Queue"="Transparent" "RenderType"="Transparent" }
+    Blend SrcAlpha OneMinusSrcAlpha
+    LOD 100
+    Pass {
+      CGPROGRAM
+      #pragma vertex vert
+      #pragma fragment frag
+
+      #include "UnityCG.cginc"
+
+      float _IntroDissolve;
+      sampler2D _MainTex;
+      float4 _MainTex_ST;
+      fixed4 _Color;
+
+      struct appdata {
+        float4 vertex : POSITION;
+        float2 uv : TEXCOORD0;
+      };
+
+      struct v2f {
+        float2 uv_MainTex : TEXCOORD0;
+        float4 vertex : SV_POSITION;
+      };
+
+      // Creates a smooth in and out line from min to max over the range t = [0, 1].
+      float smooth(float min, float max, float t) {
+        const float PI = 3.14159265358979;
+
+        // Clamp min and max to be within a certain limit of each other.
+        float limit = 3;
+        min = t < 0.5 ? min : max + limit * (saturate((min - max) / limit + 0.5) - 0.5);
+        max = t > 0.5 ? max : min + limit * (saturate((max - min) / limit + 0.5) - 0.5);
+
+        float inCurve = pow(cos(t * PI), .3);
+        float outCurve = -pow(abs(cos(t * PI)), .5);
+        return t < 0.5 ?
+            (-0.5 * inCurve + .5) * (max - min) + min :
+            (-0.5 * outCurve + .5) * (max - min) + min;
+      }
+
+      v2f vert (appdata v) {
+        v2f o;
+        o.vertex = UnityObjectToClipPos(v.vertex);
+        o.uv_MainTex = TRANSFORM_TEX(v.uv, _MainTex);
+        return o;
+      }
+
+      fixed4 frag (v2f IN) : SV_Target {
+        // Base theta is the rotational angle around the logo.
+        const float TWO_PI = 2.0 * 3.14159265358979;
+        const float PI_OVER_THREE = 3.14159265358979 / 3.0;
+        float x = IN.uv_MainTex.x - 0.5;
+        float y = IN.uv_MainTex.y - 0.5;
+        float theta = fmod(atan2(x , y) + TWO_PI - TWO_PI/21, TWO_PI);
+
+        // The commented code below was used to progress the Tilt Brush logo correctly.
+        // As Open Brush's logo is radial, this is not needed.
+
+        // Modify theta so that the first sixth of the progress sweeps across the first part of the
+        // logo.
+        // const float A_MIN = 0.600;  // Left edge of the first part of the logo
+        // const float A_MAX = 1.100;  // Right edge of the first part of the logo
+        // const float B_MIN = 0.515;  // Top edge of the first part of the logo
+        // const float B_MAX = 0.682;  // Bottom edge of the first part of the logo
+        // const float cos_30 = 0.86602540378443864676372317075294;
+        // const float sin_30 = 0.5;
+        // float a = IN.uv_MainTex.x * sin_30 + IN.uv_MainTex.y * cos_30;
+        // a = (a - A_MIN) / (A_MAX - A_MIN);
+        // float b = IN.uv_MainTex.x * sin_30 + (1 - IN.uv_MainTex.y) * cos_30;
+        // b = (b - B_MIN) / (B_MAX - B_MIN);
+
+        // // Interpolate between the three different colors in the first 1/6th of the logo.
+        // const float edge1 = 1.0 / 18;
+        // const float factor1 = _Progress / edge1;
+        // const float edge2 = 1.0 / 9;
+        // const float factor2 = (_Progress - edge1) / (edge2 - edge1);
+        // const float factor2b = -5 * (1 - factor2) + 1 * factor2;
+        // const float edge3 = 1.0 / 6;
+        // const float factor3 = (_Progress - edge2) / (edge3 - edge2);
+        // float e1 = _Progress < edge1 ? 6.65 * (1 - factor1) + 5.00 * factor1 :
+        //            _Progress < edge2 ? 5.00 * (1 - factor2) + 3.30 * factor2 : 3.30 * (1 - factor3);
+        // float e2 = _Progress < edge1 ? 3.33 * (1 - factor1) + 3.30 * factor1 :
+        //            _Progress < edge2 ? 3.30 * (1 - factor2) + 0.00 * factor2 : 0.00 * (1 - factor3);
+        // float e3 = _Progress < edge1 ? 0.00 * (1 - factor1) + 0.00 * factor1 :
+        //            _Progress < edge2 ? 0.00 * (1 - factor2) + 1.60 * factor2 : 1.60 * (1 - factor3);
+        // float e4 = _Progress < edge1 ? 3.33 * (1 - factor1) + 5.00 * factor1 :
+        //            _Progress < edge2 ? 5.00 * (1 - factor2) + 1.60 * factor2 : 1.60 * (1 - factor3);
+        // float taper =
+        //     b < 1.0 / 8 ? smooth(-e1 - 2, -e1, .5 + 4 * b) :
+        //     b < 2.0 / 8 ? smooth(-e1, -e2, 4 * b - 0.5) :
+        //     b < 3.0 / 8 ? smooth(-e1, -e2, 4 * b - 0.5) :
+        //     b < 4.0 / 8 ? smooth(-e2, -e3, 4 * b - 1.5) :
+        //     b < 5.0 / 8 ? smooth(-e2, -e3, 4 * b - 1.5) :
+        //     b < 6.0 / 8 ? smooth(-e3, -e4, 4 * b - 2.5) :
+        //     b < 7.0 / 8 ? smooth(-e3, -e4, 4 * b - 2.5) :
+        //                   smooth(-e4, -e4 - 1, 4 * b - 3.5);
+        // taper *= 0.05;
+
+        // theta = a > 0 && a < 1 && b > 0 && b < 1
+        //     ? (a + taper) * PI_OVER_THREE
+        //     : theta;
+
+        fixed4 c = tex2D(_MainTex, IN.uv_MainTex);
+        if (c.a < 0.5) discard;
+
+        c *= _Color * theta < ((1 - _IntroDissolve) * TWO_PI) ? 1 : 0.0;
+        // Uncomment out the next two lines to test out the boundaries.
+        //c.r += a > 0 && a < 1 ? .5 : 0;
+        //c.g += b > 0 && b < 1 ? .5 : 0;
+
+        return c;
+      }
+      ENDCG
+    }
+  }
+  FallBack "Diffuse"
+}

Assets/PlatformConfigMobile.asset

@@ -21,7 +21,7 @@ MonoBehaviour:
   UseFileSystemWatcher: 0
   EnableAutosave: 0
   QuickLoadMaxDistancePerFrame: 4
-  IntroSketchPrefab: {fileID: 1843608203, guid: e09adf2a1c6f67746b6db49b5e4e42f7,
+  IntroSketchPrefab: {fileID: 1843608203, guid: ddfd362fa9a8d5840bf47df17d2eba8a,
     type: 3}
   EnablePolyPreload: 0
   AvoidUploadHandlerFile: 0

Assets/PlatformConfigPC.asset

@@ -21,7 +21,7 @@ MonoBehaviour:
   UseFileSystemWatcher: 1
   EnableAutosave: 1
   QuickLoadMaxDistancePerFrame: 40
-  IntroSketchPrefab: {fileID: 1843608203, guid: aa88553059b61434b8b9958d8c222731,
+  IntroSketchPrefab: {fileID: 1843608203, guid: f9e36942d6b3ed84ba2b8b6e21505c95,
     type: 3}
   EnablePolyPreload: 1
   AvoidUploadHandlerFile: 1