secondlife/viewer#907: Local PBR terrain texture transforms

4 files changed, 228 insertions, 58 deletions

diff --git a/indra/newview/app_settings/shaders/class1/deferred/pbrterrainF.glsl b/indra/newview/app_settings/shaders/class1/deferred/pbrterrainF.glsl
index de4745c1c4..65a6b8613d 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/pbrterrainF.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/pbrterrainF.glsl
@@ -31,7 +31,7 @@
 #define TERRAIN_PBR_DETAIL_METALLIC_ROUGHNESS -3
 
 #if TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 3
-#define TerrainCoord vec4[2]
+#define TerrainCoord vec4[3]
 #elif TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 1
 #define TerrainCoord vec2
 #endif
@@ -131,12 +131,16 @@ uniform vec3[4] emissiveColors;
 uniform vec4 minimum_alphas; // PBR alphaMode: MASK, See: mAlphaCutoff, setAlphaCutoff()
 
 #if TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 3
+in vec4[10] vary_coords;
+#elif TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 1
 in vec4[2] vary_coords;
 #endif
 in vec3 vary_position;
 in vec3 vary_normal;
-in vec3 vary_tangent;
+#if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL)
+in vec3 vary_tangents[4];
 flat in float vary_sign;
+#endif
 in vec4 vary_texcoord0;
 in vec4 vary_texcoord1;
 
@@ -144,17 +148,26 @@ void mirrorClip(vec3 position);
 
 float terrain_mix(TerrainMix tm, vec4 tms4);
 
+#if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL)
+// from mikktspace.com
+vec3 mikktspace(vec3 vNt, vec3 vT)
+{
+    vec3 vN = vary_normal;
+    
+    vec3 vB = vary_sign * cross(vN, vT);
+    vec3 tnorm = normalize( vNt.x * vT + vNt.y * vB + vNt.z * vN );
+
+    tnorm *= gl_FrontFacing ? 1.0 : -1.0;
+
+    return tnorm;
+}
+#endif
+
 void main()
 {
     // Make sure we clip the terrain if we're in a mirror.
     mirrorClip(vary_position);
 
-#if TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 3
-    TerrainCoord terrain_texcoord = vary_coords;
-#elif TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 1
-    TerrainCoord terrain_texcoord = vary_texcoord0.xy;
-#endif
-
     float alpha1 = texture(alpha_ramp, vary_texcoord0.zw).a;
     float alpha2 = texture(alpha_ramp,vary_texcoord1.xy).a;
     float alphaFinal = texture(alpha_ramp, vary_texcoord1.zw).a;
@@ -185,6 +198,16 @@ void main()
     switch (tm.type & MIX_X)
     {
     case MIX_X:
+#if TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 3
+        TerrainCoord terrain_texcoord;
+        terrain_texcoord[0].xy = vary_coords[0].xy;
+        terrain_texcoord[0].zw = vary_coords[0].zw;
+        terrain_texcoord[1].xy = vary_coords[1].xy;
+        terrain_texcoord[1].zw = vary_coords[1].zw;
+        terrain_texcoord[2].xy = vary_coords[2].xy;
+#elif TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 1
+        TerrainCoord terrain_texcoord = vary_coords[0].xy;
+#endif
         mix2 = terrain_sample_and_multiply_pbr(
             terrain_texcoord
             , detail_0_base_color
@@ -207,6 +230,9 @@ void main()
             , emissiveColors[0]
 #endif
         );
+#if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL)
+        mix2.vNt = mikktspace(mix2.vNt, vary_tangents[0]);
+#endif
         mix = mix_pbr(mix, mix2, tm.weight.x);
         break;
     default:
@@ -215,6 +241,16 @@ void main()
     switch (tm.type & MIX_Y)
     {
     case MIX_Y:
+#if TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 3
+        TerrainCoord terrain_texcoord;
+        terrain_texcoord[0].xy = vary_coords[2].zw;
+        terrain_texcoord[0].zw = vary_coords[3].xy;
+        terrain_texcoord[1].xy = vary_coords[3].zw;
+        terrain_texcoord[1].zw = vary_coords[4].xy;
+        terrain_texcoord[2].xy = vary_coords[4].zw;
+#elif TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 1
+        TerrainCoord terrain_texcoord = vary_coords[0].zw;
+#endif
         mix2 = terrain_sample_and_multiply_pbr(
             terrain_texcoord
             , detail_1_base_color
@@ -237,6 +273,9 @@ void main()
             , emissiveColors[1]
 #endif
         );
+#if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL)
+        mix2.vNt = mikktspace(mix2.vNt, vary_tangents[1]);
+#endif
         mix = mix_pbr(mix, mix2, tm.weight.y);
         break;
     default:
@@ -245,6 +284,16 @@ void main()
     switch (tm.type & MIX_Z)
     {
     case MIX_Z:
+#if TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 3
+        TerrainCoord terrain_texcoord;
+        terrain_texcoord[0].xy = vary_coords[5].xy;
+        terrain_texcoord[0].zw = vary_coords[5].zw;
+        terrain_texcoord[1].xy = vary_coords[6].xy;
+        terrain_texcoord[1].zw = vary_coords[6].zw;
+        terrain_texcoord[2].xy = vary_coords[7].xy;
+#elif TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 1
+        TerrainCoord terrain_texcoord = vary_coords[1].xy;
+#endif
         mix2 = terrain_sample_and_multiply_pbr(
             terrain_texcoord
             , detail_2_base_color
@@ -267,6 +316,9 @@ void main()
             , emissiveColors[2]
 #endif
         );
+#if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL)
+        mix2.vNt = mikktspace(mix2.vNt, vary_tangents[2]);
+#endif
         mix = mix_pbr(mix, mix2, tm.weight.z);
         break;
     default:
@@ -275,6 +327,16 @@ void main()
     switch (tm.type & MIX_W)
     {
     case MIX_W:
+#if TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 3
+        TerrainCoord terrain_texcoord;
+        terrain_texcoord[0].xy = vary_coords[7].zw;
+        terrain_texcoord[0].zw = vary_coords[8].xy;
+        terrain_texcoord[1].xy = vary_coords[8].zw;
+        terrain_texcoord[1].zw = vary_coords[9].xy;
+        terrain_texcoord[2].xy = vary_coords[9].zw;
+#elif TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 1
+        TerrainCoord terrain_texcoord = vary_coords[1].zw;
+#endif
         mix2 = terrain_sample_and_multiply_pbr(
             terrain_texcoord
             , detail_3_base_color
@@ -297,6 +359,9 @@ void main()
             , emissiveColors[3]
 #endif
         );
+#if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL)
+        mix2.vNt = mikktspace(mix2.vNt, vary_tangents[3]);
+#endif
         mix = mix_pbr(mix, mix2, tm.weight.w);
         break;
     default:
@@ -311,19 +376,11 @@ void main()
     float base_color_factor_alpha = terrain_mix(tm, vec4(baseColorFactors[0].z, baseColorFactors[1].z, baseColorFactors[2].z, baseColorFactors[3].z));
 
 #if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL)
-    // from mikktspace.com
-    vec3 vNt = mix.vNt;
-    vec3 vN = vary_normal;
-    vec3 vT = vary_tangent.xyz;
-    
-    vec3 vB = vary_sign * cross(vN, vT);
-    vec3 tnorm = normalize( vNt.x * vT + vNt.y * vB + vNt.z * vN );
-
-    tnorm *= gl_FrontFacing ? 1.0 : -1.0;
+    vec3 tnorm = normalize(mix.vNt);
 #else
     vec3 tnorm = vary_normal;
-    tnorm *= gl_FrontFacing ? 1.0 : -1.0;
 #endif
+    tnorm *= gl_FrontFacing ? 1.0 : -1.0;
    
 
 #if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_EMISSIVE)
diff --git a/indra/newview/app_settings/shaders/class1/deferred/pbrterrainUtilF.glsl b/indra/newview/app_settings/shaders/class1/deferred/pbrterrainUtilF.glsl
index 935c3f9301..7a7fd783ec 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/pbrterrainUtilF.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/pbrterrainUtilF.glsl
@@ -233,17 +233,12 @@ float terrain_mix(TerrainMix tm, vec4 tms4)
 // Triplanar mapping
 
 // Pre-transformed texture coordinates for each axial uv slice (Packing: xy, yz, (-x)z, unused)
-#define TerrainCoord vec4[2]
+#define TerrainCoord vec4[3]
 
-vec2 _t_uv(vec2 uv_unflipped, float sign_or_zero)
+// If sign_or_zero is positive, use uv_unflippped, otherwise use uv_flipped
+vec2 _t_uv(vec2 uv_unflipped, vec2 uv_flipped, float sign_or_zero)
 {
-    // Handle case where sign is 0
-    float sign = (2.0*sign_or_zero) + 1.0;
-    sign /= abs(sign);
-    // If the vertex normal is negative, flip the texture back
-    // right-side up.
-    vec2 uv = uv_unflipped * vec2(sign, 1);
-    return uv;
+    return mix(uv_flipped, uv_unflipped, max(0.0, sign_or_zero));
 }
 
 vec3 _t_normal_post_1(vec3 vNt0, float sign_or_zero)
@@ -298,9 +293,9 @@ PBRMix terrain_sample_pbr(
 {
     PBRMix mix = init_pbr_mix();
 
-#define get_uv_x() _t_uv(terrain_coord[0].zw, sign(vary_vertex_normal.x))
-#define get_uv_y() _t_uv(terrain_coord[1].xy, sign(vary_vertex_normal.y))
-#define get_uv_z() _t_uv(terrain_coord[0].xy, sign(vary_vertex_normal.z))
+#define get_uv_x() _t_uv(terrain_coord[0].zw, terrain_coord[1].zw, sign(vary_vertex_normal.x))
+#define get_uv_y() _t_uv(terrain_coord[1].xy, terrain_coord[2].xy, sign(vary_vertex_normal.y))
+#define get_uv_z() _t_uv(terrain_coord[0].xy, vec2(0),             sign(vary_vertex_normal.z))
     switch (tw.type & SAMPLE_X)
     {
     case SAMPLE_X:
diff --git a/indra/newview/app_settings/shaders/class1/deferred/pbrterrainV.glsl b/indra/newview/app_settings/shaders/class1/deferred/pbrterrainV.glsl
index 489fc26e3f..167d980eb8 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/pbrterrainV.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/pbrterrainV.glsl
@@ -23,6 +23,11 @@
  * $/LicenseInfo$
  */
 
+#define TERRAIN_PBR_DETAIL_EMISSIVE 0
+#define TERRAIN_PBR_DETAIL_OCCLUSION -1
+#define TERRAIN_PBR_DETAIL_NORMAL -2
+#define TERRAIN_PBR_DETAIL_METALLIC_ROUGHNESS -3
+
 uniform mat3 normal_matrix;
 uniform mat4 texture_matrix0;
 uniform mat4 modelview_matrix;
@@ -34,24 +39,28 @@ in vec4 tangent;
 in vec4 diffuse_color;
 in vec2 texcoord1;
 
-#if TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 3
-out vec4[2] vary_coords;
-#endif
 out vec3 vary_vertex_normal; // Used by pbrterrainUtilF.glsl
 out vec3 vary_normal;
-out vec3 vary_tangent;
+#if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL)
+out vec3 vary_tangents[4];
 flat out float vary_sign;
+#endif
 out vec4 vary_texcoord0;
 out vec4 vary_texcoord1;
+#if TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 3
+out vec4[10] vary_coords;
+#elif TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 1
+out vec4[2] vary_coords;
+#endif
 out vec3 vary_position;
 
-// *HACK: tangent_space_transform should use texture_normal_transform, or maybe
-// we shouldn't use tangent_space_transform at all. See the call to
-// tangent_space_transform below.
-uniform vec4[2] texture_base_color_transform;
+// *HACK: Each material uses only one texture transform, but the KHR texture
+// transform spec allows handling texture transforms separately for each
+// individual texture info.
+uniform vec4[5] terrain_texture_transforms;
 
-vec2 texture_transform(vec2 vertex_texcoord, vec4[2] khr_gltf_transform, mat4 sl_animation_transform);
-vec3 tangent_space_transform(vec4 vertex_tangent, vec3 vertex_normal, vec4[2] khr_gltf_transform, mat4 sl_animation_transform);
+vec2 terrain_texture_transform(vec2 vertex_texcoord, vec4[2] khr_gltf_transform);
+vec3 terrain_tangent_space_transform(vec4 vertex_tangent, vec3 vertex_normal, vec4[2] khr_gltf_transform);
 
 void main()
 {
@@ -63,31 +72,101 @@ void main()
     vary_vertex_normal = normal;
 	vec3 t = normal_matrix * tangent.xyz;
 
-    vary_tangent = normalize(t);
-    // *TODO: Decide if we want this. It may be better to just calculate the
-    // tangents on-the-fly in the fragment shader, due to the subtleties of the
-    // effect of triplanar mapping on UVs.
-    // *HACK: Should be using texture_normal_transform here. The KHR texture
-    // transform spec requires handling texture transforms separately for each
-    // individual texture.
-    vary_tangent = normalize(tangent_space_transform(vec4(t, tangent.w), n, texture_base_color_transform, texture_matrix0));
+#if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL)
+    {
+        vec4[2] ttt;
+        // material 1
+        ttt[0].xyz = terrain_texture_transforms[0].xyz;
+        ttt[1].x = terrain_texture_transforms[0].w;
+        ttt[1].y = terrain_texture_transforms[1].x;
+        vary_tangents[0] = normalize(terrain_tangent_space_transform(vec4(t, tangent.w), n, ttt));
+        // material 2
+        ttt[0].xyz = terrain_texture_transforms[1].yzw;
+        ttt[1].xy = terrain_texture_transforms[2].xy;
+        vary_tangents[1] = normalize(terrain_tangent_space_transform(vec4(t, tangent.w), n, ttt));
+        // material 3
+        ttt[0].xy = terrain_texture_transforms[2].zw;
+        ttt[0].z = terrain_texture_transforms[3].x;
+        ttt[1].xy = terrain_texture_transforms[3].yz;
+        vary_tangents[2] = normalize(terrain_tangent_space_transform(vec4(t, tangent.w), n, ttt));
+        // material 4
+        ttt[0].x = terrain_texture_transforms[3].w;
+        ttt[0].yz = terrain_texture_transforms[4].xy;
+        ttt[1].xy = terrain_texture_transforms[4].zw;
+        vary_tangents[3] = normalize(terrain_tangent_space_transform(vec4(t, tangent.w), n, ttt));
+    }
+
     vary_sign = tangent.w;
+#endif
     vary_normal = normalize(n);
 
     // Transform and pass tex coords
-    // *HACK: texture_base_color_transform is used for all of these here, but
-    // the KHR texture transform spec requires handling texture transforms
-    // separately for each individual texture.
+    {
+        vec4[2] ttt;
 #if TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 3
-    // xy
-    vary_coords[0].xy = texture_transform(position.xy, texture_base_color_transform, texture_matrix0);
-    // yz
-    vary_coords[0].zw = texture_transform(position.yz, texture_base_color_transform, texture_matrix0);
-    // (-x)z
-    vary_coords[1].xy = texture_transform(position.xz * vec2(-1, 1), texture_base_color_transform, texture_matrix0);
+// Don't care about upside-down (transform_xy_flipped())
+#define transform_xy()             terrain_texture_transform(position.xy,               ttt)
+#define transform_yz()             terrain_texture_transform(position.yz,               ttt)
+#define transform_negx_z()         terrain_texture_transform(position.xz * vec2(-1, 1), ttt)
+#define transform_yz_flipped()     terrain_texture_transform(position.yz * vec2(-1, 1), ttt)
+#define transform_negx_z_flipped() terrain_texture_transform(position.xz,               ttt)
+        // material 1
+        ttt[0].xyz = terrain_texture_transforms[0].xyz;
+        ttt[1].x = terrain_texture_transforms[0].w;
+        ttt[1].y = terrain_texture_transforms[1].x;
+        vary_coords[0].xy = transform_xy();
+        vary_coords[0].zw = transform_yz();
+        vary_coords[1].xy = transform_negx_z();
+        vary_coords[1].zw = transform_yz_flipped();
+        vary_coords[2].xy = transform_negx_z_flipped();
+        // material 2
+        ttt[0].xyz = terrain_texture_transforms[1].yzw;
+        ttt[1].xy = terrain_texture_transforms[2].xy;
+        vary_coords[2].zw = transform_xy();
+        vary_coords[3].xy = transform_yz();
+        vary_coords[3].zw = transform_negx_z();
+        vary_coords[4].xy = transform_yz_flipped();
+        vary_coords[4].zw = transform_negx_z_flipped();
+        // material 3
+        ttt[0].xy = terrain_texture_transforms[2].zw;
+        ttt[0].z = terrain_texture_transforms[3].x;
+        ttt[1].xy = terrain_texture_transforms[3].yz;
+        vary_coords[5].xy = transform_xy();
+        vary_coords[5].zw = transform_yz();
+        vary_coords[6].xy = transform_negx_z();
+        vary_coords[6].zw = transform_yz_flipped();
+        vary_coords[7].xy = transform_negx_z_flipped();
+        // material 4
+        ttt[0].x = terrain_texture_transforms[3].w;
+        ttt[0].yz = terrain_texture_transforms[4].xy;
+        ttt[1].xy = terrain_texture_transforms[4].zw;
+        vary_coords[7].zw = transform_xy();
+        vary_coords[8].xy = transform_yz();
+        vary_coords[8].zw = transform_negx_z();
+        vary_coords[9].xy = transform_yz_flipped();
+        vary_coords[9].zw = transform_negx_z_flipped();
 #elif TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 1
-    vary_texcoord0.xy = texture_transform(position.xy, texture_base_color_transform, texture_matrix0);
+        // material 1
+        ttt[0].xyz = terrain_texture_transforms[0].xyz;
+        ttt[1].x = terrain_texture_transforms[0].w;
+        ttt[1].y = terrain_texture_transforms[1].x;
+        vary_coords[0].xy = terrain_texture_transform(position.xy, ttt);
+        // material 2
+        ttt[0].xyz = terrain_texture_transforms[1].yzw;
+        ttt[1].xy = terrain_texture_transforms[2].xy;
+        vary_coords[0].zw = terrain_texture_transform(position.xy, ttt);
+        // material 3
+        ttt[0].xy = terrain_texture_transforms[2].zw;
+        ttt[0].z = terrain_texture_transforms[3].x;
+        ttt[1].xy = terrain_texture_transforms[3].yz;
+        vary_coords[1].xy = terrain_texture_transform(position.xy, ttt);
+        // material 4
+        ttt[0].x = terrain_texture_transforms[3].w;
+        ttt[0].yz = terrain_texture_transforms[4].xy;
+        ttt[1].xy = terrain_texture_transforms[4].zw;
+        vary_coords[1].zw = terrain_texture_transform(position.xy, ttt);
 #endif
+    }
     
     vec4 tc = vec4(texcoord1,0,1);
     vary_texcoord0.zw = tc.xy;
diff --git a/indra/newview/app_settings/shaders/class1/deferred/textureUtilV.glsl b/indra/newview/app_settings/shaders/class1/deferred/textureUtilV.glsl
index 732333311c..baf4010fa7 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/textureUtilV.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/textureUtilV.glsl
@@ -48,6 +48,7 @@ vec2 khr_texture_transform(vec2 texcoord, vec2 scale, float rotation, vec2 offse
     return (transform * vec3(texcoord, 1)).xy;
 }
 
+// A texture transform function for PBR materials applied to shape prims/Collada model prims
 // vertex_texcoord - The UV texture coordinates sampled from the vertex at
 //     runtime. Per SL convention, this is in a right-handed UV coordinate
 //     system. Collada models also have right-handed UVs.
@@ -77,6 +78,21 @@ vec2 texture_transform(vec2 vertex_texcoord, vec4[2] khr_gltf_transform, mat4 sl
     return texcoord;
 }
 
+// Similar to texture_transform but no offset during coordinate system
+// conversion, and no texture animation support.
+vec2 terrain_texture_transform(vec2 vertex_texcoord, vec4[2] khr_gltf_transform)
+{
+    vec2 texcoord = vertex_texcoord;
+
+    texcoord.y = 1.0 - texcoord.y;
+    //texcoord.y = -texcoord.y;
+    texcoord = khr_texture_transform(texcoord, khr_gltf_transform[0].xy, khr_gltf_transform[0].z, khr_gltf_transform[1].xy);
+    texcoord.y = 1.0 - texcoord.y;
+    //texcoord.y = -texcoord.y;
+
+    return texcoord;
+}
+
 // Take the rotation only from both transforms and apply to the tangent. This
 // accounts for the change of the topology of the normal texture when a texture
 // rotation is applied to it.
@@ -120,3 +136,26 @@ vec3 tangent_space_transform(vec4 vertex_tangent, vec3 vertex_normal, vec4[2] kh
 
     return (weights.x * vertex_binormal.xyz) + (weights.y * vertex_tangent.xyz);
 }
+
+// Similar to tangent_space_transform but no offset during coordinate system
+// conversion, and no texture animation support.
+vec3 terrain_tangent_space_transform(vec4 vertex_tangent, vec3 vertex_normal, vec4[2] khr_gltf_transform)
+{
+    // Immediately convert to left-handed coordinate system ((0,1) -> (0, -1))
+    vec2 weights = vec2(0, -1);
+
+    // Apply KHR_texture_transform (rotation only)
+    float khr_rotation = khr_gltf_transform[0].z;
+    mat2 khr_rotation_mat = mat2(
+        cos(khr_rotation),-sin(khr_rotation),
+        sin(khr_rotation), cos(khr_rotation)
+    );
+    weights = khr_rotation_mat * weights;
+
+    // Convert back to right-handed coordinate system
+    weights.y = -weights.y;
+
+    vec3 vertex_binormal = vertex_tangent.w * cross(vertex_normal, vertex_tangent.xyz);
+
+    return (weights.x * vertex_binormal.xyz) + (weights.y * vertex_tangent.xyz);
+}