Restore support for wavy avatar cloth(#4963)

Signed-off-by: Rye <rye@alchemyviewer.org>

2 files changed, 79 insertions, 5 deletions

diff --git a/indra/newview/app_settings/settings.xml b/indra/newview/app_settings/settings.xml
index aca9910253..ebb3158ca7 100644
--- a/indra/newview/app_settings/settings.xml
+++ b/indra/newview/app_settings/settings.xml
@@ -7263,7 +7263,7 @@
   <key>RenderAvatarCloth</key>
     <map>
       <key>Comment</key>
-      <string>DEPRECATED - only false supported - Controls if avatars use wavy cloth</string>
+      <string>Controls if system avatar clothes use wavy cloth</string>
       <key>Persist</key>
       <integer>1</integer>
       <key>Type</key>
diff --git a/indra/newview/app_settings/shaders/class1/deferred/avatarV.glsl b/indra/newview/app_settings/shaders/class1/deferred/avatarV.glsl
index aabbbac12a..1b1233790e 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/avatarV.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/avatarV.glsl
@@ -28,6 +28,9 @@ uniform mat4 projection_matrix;
 in vec3 position;
 in vec3 normal;
 in vec2 texcoord0;
+#ifdef AVATAR_CLOTH
+in vec4 clothing;
+#endif
 
 mat4 getSkinnedTransform();
 
@@ -37,6 +40,15 @@ out vec3 vary_normal;
 out vec2 vary_texcoord0;
 out vec3 vary_position;
 
+#ifdef AVATAR_CLOTH
+uniform vec4 gWindDir;
+uniform vec4 gSinWaveParams;
+uniform vec4 gGravity;
+
+const vec4 gMinMaxConstants = vec4(1.0, 0.166666, 0.0083143, .00018542);     // #minimax-generated coefficients
+const vec4 gPiConstants = vec4(0.159154943, 6.28318530, 3.141592653, 1.5707963); // # {1/2PI, 2PI, PI, PI/2}
+#endif
+
 void main()
 {
     vary_texcoord0 = texcoord0;
@@ -46,16 +58,78 @@ void main()
 
     vec4 pos_in = vec4(position.xyz, 1.0);
     mat4 trans = getSkinnedTransform();
-    pos.x = dot(trans[0], pos_in);
-    pos.y = dot(trans[1], pos_in);
-    pos.z = dot(trans[2], pos_in);
-    pos.w = 1.0;
 
     norm.x = dot(trans[0].xyz, normal);
     norm.y = dot(trans[1].xyz, normal);
     norm.z = dot(trans[2].xyz, normal);
     norm = normalize(norm);
 
+#ifdef AVATAR_CLOTH
+    //wind
+    vec4 windEffect;
+    windEffect = vec4(dot(norm, gWindDir.xyz));
+    pos.x = dot(trans[2], pos_in);
+    windEffect.xyz = pos.x * vec3(0.015, 0.015, 0.015)
+                        + windEffect.xyz;
+    windEffect.w = windEffect.w * 2.0 + 1.0;                // move wind offset value to [-1, 3]
+    windEffect.w = windEffect.w*gWindDir.w;                 // modulate wind strength
+
+    windEffect.xyz = windEffect.xyz*gSinWaveParams.xyz
+                        +vec3(gSinWaveParams.w);            // use sin wave params to scale and offset input
+
+    //reduce to period of 2 PI
+    vec4 temp1, temp0, temp2, offsetPos;
+    temp1.xyz = windEffect.xyz * gPiConstants.x;            // change input as multiple of [0-2PI] to [0-1]
+    temp0.y = mod(temp1.x,1.0);
+    windEffect.x = temp0.y * gPiConstants.y;                // scale from [0,1] to [0, 2PI]
+    temp1.z = temp1.z - gPiConstants.w;                     // shift normal oscillation by PI/2
+    temp0.y = mod(temp1.z,1.0);
+
+    windEffect.z = temp0.y * gPiConstants.y;                // scale from [0,1] to [0, 2PI]
+    windEffect.xyz = windEffect.xyz + vec3(-3.141592);      // offset to [-PI, PI]
+
+    //calculate sinusoid
+    vec4 sinWave;
+    temp1 = windEffect*windEffect;
+    sinWave = -temp1 * gMinMaxConstants.w
+                + vec4(gMinMaxConstants.z);                 // y = -(x^2)/7! + 1/5!
+    sinWave = sinWave * -temp1 + vec4(gMinMaxConstants.y);  // y = -(x^2) * (-(x^2)/7! + 1/5!) + 1/3!
+    sinWave = sinWave * -temp1 + vec4(gMinMaxConstants.x);  // y = -(x^2) * (-(x^2) * (-(x^2)/7! + 1/5!) + 1/3!) + 1
+    sinWave = sinWave * windEffect;                         // y = x * (-(x^2) * (-(x^2) * (-(x^2)/7! + 1/5!) + 1/3!) + 1)
+
+    // sinWave.x holds sin(norm . wind_direction) with primary frequency
+    // sinWave.y holds sin(norm . wind_direction) with secondary frequency
+    // sinWave.z hold cos(norm . wind_direction) with primary frequency
+    sinWave.xyz = sinWave.xyz * gWindDir.w
+                + vec3(windEffect.w);                       // multiply by wind strength in gWindDir.w [-wind, wind]
+
+    // add normal facing bias offset [-wind,wind] -> [-wind - .25, wind + 1]
+    temp1 = vec4(dot(norm, gGravity.xyz));                  // how much is this normal facing in direction of gGravity?
+    temp1 = min(temp1, vec4(0.2,0.0,0.0,0.0));              // clamp [-1, 1] to [-1, 0.2]
+    temp1 = temp1*vec4(1.5,0.0,0.0,0.0);                    // scale from [-1,0.2] to [-1.5, 0.3]
+    sinWave.x = sinWave.x + temp1.x;                        // add gGravity effect to sinwave (only primary frequency)
+    sinWave.xyz = sinWave.xyz * clothing.w;                 // modulate by clothing coverage
+
+    sinWave.xyz = max(sinWave.xyz, vec3(-1.0, -1.0, -1.0)); // clamp to underlying body shape
+    offsetPos = clothing * sinWave.x;                       // multiply wind effect times clothing displacement
+    temp2 = gWindDir*sinWave.z + vec4(norm,0);              // calculate normal offset due to wind oscillation
+    offsetPos = vec4(1.0,1.0,1.0,0.0)*offsetPos+pos_in;     // add to offset vertex position, and zero out effect from w
+    norm += temp2.xyz*2.0;                                  // add sin wave effect on normals (exaggerated)
+
+    //renormalize normal (again)
+    norm = normalize(norm);
+
+    pos.x = dot(trans[0], offsetPos);
+    pos.y = dot(trans[1], offsetPos);
+    pos.z = dot(trans[2], offsetPos);
+    pos.w = 1.0;
+#else
+    pos.x = dot(trans[0], pos_in);
+    pos.y = dot(trans[1], pos_in);
+    pos.z = dot(trans[2], pos_in);
+    pos.w = 1.0;
+#endif
+
     vary_normal = norm;
 
     vary_position = pos.xyz;