Adding ViroKit. Needs AWSCore :(

mobile/ios/ViroKit.framework/skinning_vsh.glsl

@@ -0,0 +1,56 @@
+layout (std140) uniform bones {
+    mat4 bone_matrices[192];
+};
+
+layout (std140) uniform bones_dq {
+    vec4 bone_transforms_dq[192 * 3];
+};
+
+vec4 get_blended_scale(ivec4 bone_indices, vec4 bone_weights) {
+    vec4 s0 = bone_transforms_dq[bone_indices.x * 3 + 2];
+    vec4 s1 = bone_transforms_dq[bone_indices.y * 3 + 2];
+    vec4 s2 = bone_transforms_dq[bone_indices.z * 3 + 2];
+    vec4 s3 = bone_transforms_dq[bone_indices.w * 3 + 2];
+    
+    vec4 blended_s = s0 * bone_weights.x +
+                     s1 * bone_weights.y +
+                     s2 * bone_weights.z +
+                     s3 * bone_weights.w;
+    return blended_s;
+}
+
+mat2x4 get_bone_dual_quaternion(int bone_index) {
+    return mat2x4(bone_transforms_dq[bone_index * 3 + 0],
+                  bone_transforms_dq[bone_index * 3 + 1]);
+}
+
+mat2x4 get_blended_dual_quaternion(ivec4 bone_indices, vec4 bone_weights) {
+    mat2x4 dq0 = get_bone_dual_quaternion(bone_indices.x);
+    mat2x4 dq1 = get_bone_dual_quaternion(bone_indices.y);
+    mat2x4 dq2 = get_bone_dual_quaternion(bone_indices.z);
+    mat2x4 dq3 = get_bone_dual_quaternion(bone_indices.w);
+    
+    if (dot(dq0[0], dq1[0]) < 0.0) bone_weights.y *= -1.0;
+    if (dot(dq0[0], dq2[0]) < 0.0) bone_weights.z *= -1.0;
+    if (dot(dq0[0], dq3[0]) < 0.0) bone_weights.w *= -1.0;
+    
+    mat2x4 blended_dq = dq0 * bone_weights.x +
+                        dq1 * bone_weights.y +
+                        dq2 * bone_weights.z +
+                        dq3 * bone_weights.w;
+    
+    float norm = length(blended_dq[0]);
+    return blended_dq / norm;
+}
+
+vec3 quat_rotate_vector(vec3 v, vec4 real_dq) {
+    return v + 2.0 * cross(real_dq.w * v + cross(v, real_dq.xyz), real_dq.xyz);
+}
+
+vec3 dual_quat_transform_point(vec3 p, vec4 real_dq, vec4 dual_dq) {
+    // Reconstruct translation from the dual quaternion
+    vec3 t = 2.0 * (real_dq.w * dual_dq.xyz - dual_dq.w * real_dq.xyz + cross(real_dq.xyz, dual_dq.xyz));
+
+    // Combine with rotation of the input point
+    return quat_rotate_vector(p, real_dq) + t;
+}