From 5a60b7811fb666f2ef59abc57a3204297f6aaa1a Mon Sep 17 00:00:00 2001 From: Cosmic Linden Date: Fri, 28 Jun 2024 14:54:53 -0700 Subject: secondlife/viewer#1847: Fix wrong lighting for negative texture scale on PBR materials and PBR terrain --- .../shaders/class1/deferred/pbralphaV.glsl | 7 +- .../shaders/class1/deferred/pbropaqueV.glsl | 7 +- .../shaders/class1/deferred/pbrterrainF.glsl | 29 +++++++-- .../shaders/class1/deferred/pbrterrainUtilF.glsl | 12 +++- .../shaders/class1/deferred/pbrterrainV.glsl | 23 ++++--- .../shaders/class1/deferred/textureUtilV.glsl | 74 +++++++++++++++------- 6 files changed, 105 insertions(+), 47 deletions(-) diff --git a/indra/newview/app_settings/shaders/class1/deferred/pbralphaV.glsl b/indra/newview/app_settings/shaders/class1/deferred/pbralphaV.glsl index ae179d3f37..66adf50fa9 100644 --- a/indra/newview/app_settings/shaders/class1/deferred/pbralphaV.glsl +++ b/indra/newview/app_settings/shaders/class1/deferred/pbralphaV.glsl @@ -69,7 +69,7 @@ flat out float vary_sign; out vec3 vary_normal; 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); +vec4 tangent_space_transform(vec4 vertex_tangent, vec3 vertex_normal, vec4[2] khr_gltf_transform, mat4 sl_animation_transform); void main() @@ -103,8 +103,9 @@ void main() n = normalize(n); - vary_tangent = normalize(tangent_space_transform(vec4(t, tangent.w), n, texture_normal_transform, texture_matrix0)); - vary_sign = tangent.w; + vec4 transformed_tangent = tangent_space_transform(vec4(t, tangent.w), n, texture_normal_transform, texture_matrix0); + vary_tangent = normalize(transformed_tangent.xyz); + vary_sign = transformed_tangent.w; vary_normal = n; vertex_color = diffuse_color; diff --git a/indra/newview/app_settings/shaders/class1/deferred/pbropaqueV.glsl b/indra/newview/app_settings/shaders/class1/deferred/pbropaqueV.glsl index fd020afd57..0ad9bf5e4b 100644 --- a/indra/newview/app_settings/shaders/class1/deferred/pbropaqueV.glsl +++ b/indra/newview/app_settings/shaders/class1/deferred/pbropaqueV.glsl @@ -63,7 +63,7 @@ out vec3 vary_normal; out vec3 vary_position; 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); +vec4 tangent_space_transform(vec4 vertex_tangent, vec3 vertex_normal, vec4[2] khr_gltf_transform, mat4 sl_animation_transform); void main() { @@ -97,8 +97,9 @@ void main() n = normalize(n); - vary_tangent = normalize(tangent_space_transform(vec4(t, tangent.w), n, texture_normal_transform, texture_matrix0)); - vary_sign = tangent.w; + vec4 transformed_tangent = tangent_space_transform(vec4(t, tangent.w), n, texture_normal_transform, texture_matrix0); + vary_tangent = normalize(transformed_tangent.xyz); + vary_sign = transformed_tangent.w; vary_normal = n; vertex_color = diffuse_color; diff --git a/indra/newview/app_settings/shaders/class1/deferred/pbrterrainF.glsl b/indra/newview/app_settings/shaders/class1/deferred/pbrterrainF.glsl index 2cb7ff196b..6ca35419f2 100644 --- a/indra/newview/app_settings/shaders/class1/deferred/pbrterrainF.glsl +++ b/indra/newview/app_settings/shaders/class1/deferred/pbrterrainF.glsl @@ -75,6 +75,9 @@ PBRMix terrain_sample_and_multiply_pbr( #endif #if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL) , sampler2D tex_vNt +#if TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 3 + , float transform_sign +#endif #endif #if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_EMISSIVE) , sampler2D tex_emissive @@ -139,7 +142,7 @@ in vec3 vary_position; in vec3 vary_normal; #if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL) in vec3 vary_tangents[4]; -flat in float vary_sign; +flat in float vary_signs[4]; #endif in vec4 vary_texcoord0; in vec4 vary_texcoord1; @@ -150,11 +153,11 @@ 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 mikktspace(vec3 vNt, vec3 vT, float sign) { vec3 vN = vary_normal; - vec3 vB = vary_sign * cross(vN, vT); + vec3 vB = sign * cross(vN, vT); vec3 tnorm = normalize( vNt.x * vT + vNt.y * vB + vNt.z * vN ); tnorm *= gl_FrontFacing ? 1.0 : -1.0; @@ -216,6 +219,9 @@ void main() #endif #if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL) , detail_0_normal +#if TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 3 + , vary_signs[0] +#endif #endif #if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_EMISSIVE) , detail_0_emissive @@ -231,7 +237,7 @@ void main() #endif ); #if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL) - mix2.vNt = mikktspace(mix2.vNt, vary_tangents[0]); + mix2.vNt = mikktspace(mix2.vNt, vary_tangents[0], vary_signs[0]); #endif pbr_mix = mix_pbr(pbr_mix, mix2, tm.weight.x); break; @@ -258,6 +264,9 @@ void main() #endif #if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL) , detail_1_normal +#if TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 3 + , vary_signs[1] +#endif #endif #if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_EMISSIVE) , detail_1_emissive @@ -273,7 +282,7 @@ void main() #endif ); #if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL) - mix2.vNt = mikktspace(mix2.vNt, vary_tangents[1]); + mix2.vNt = mikktspace(mix2.vNt, vary_tangents[1], vary_signs[1]); #endif pbr_mix = mix_pbr(pbr_mix, mix2, tm.weight.y); break; @@ -300,6 +309,9 @@ void main() #endif #if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL) , detail_2_normal +#if TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 3 + , vary_signs[2] +#endif #endif #if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_EMISSIVE) , detail_2_emissive @@ -315,7 +327,7 @@ void main() #endif ); #if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL) - mix2.vNt = mikktspace(mix2.vNt, vary_tangents[2]); + mix2.vNt = mikktspace(mix2.vNt, vary_tangents[2], vary_signs[2]); #endif pbr_mix = mix_pbr(pbr_mix, mix2, tm.weight.z); break; @@ -342,6 +354,9 @@ void main() #endif #if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL) , detail_3_normal +#if TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 3 + , vary_signs[3] +#endif #endif #if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_EMISSIVE) , detail_3_emissive @@ -357,7 +372,7 @@ void main() #endif ); #if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL) - mix2.vNt = mikktspace(mix2.vNt, vary_tangents[3]); + mix2.vNt = mikktspace(mix2.vNt, vary_tangents[3], vary_signs[3]); #endif pbr_mix = mix_pbr(pbr_mix, mix2, tm.weight.w); break; diff --git a/indra/newview/app_settings/shaders/class1/deferred/pbrterrainUtilF.glsl b/indra/newview/app_settings/shaders/class1/deferred/pbrterrainUtilF.glsl index 1ae9efe544..5098de717e 100644 --- a/indra/newview/app_settings/shaders/class1/deferred/pbrterrainUtilF.glsl +++ b/indra/newview/app_settings/shaders/class1/deferred/pbrterrainUtilF.glsl @@ -256,11 +256,12 @@ vec3 _t_normal_post_1(vec3 vNt0, float sign_or_zero) } // Triplanar-specific normal texture fixes -vec3 _t_normal_post_x(vec3 vNt0) +vec3 _t_normal_post_x(vec3 vNt0, float tangent_sign) { vec3 vNt_x = _t_normal_post_1(vNt0, sign(vary_vertex_normal.x)); // *HACK: Transform normals according to orientation of the UVs vNt_x.xy = vec2(-vNt_x.y, vNt_x.x); + vNt_x.xy *= tangent_sign; return vNt_x; } vec3 _t_normal_post_y(vec3 vNt0) @@ -285,6 +286,7 @@ PBRMix terrain_sample_pbr( #endif #if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL) , sampler2D tex_vNt + , float tangent_sign #endif #if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_EMISSIVE) , sampler2D tex_emissive @@ -314,7 +316,7 @@ PBRMix terrain_sample_pbr( ); #if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL) // Triplanar-specific normal texture fix - mix_x.vNt = _t_normal_post_x(mix_x.vNt); + mix_x.vNt = _t_normal_post_x(mix_x.vNt, tangent_sign); #endif mix = mix_pbr(mix, mix_x, tw.weight.x); break; @@ -420,6 +422,9 @@ PBRMix terrain_sample_and_multiply_pbr( #endif #if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL) , sampler2D tex_vNt +#if TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 3 + , float tangent_sign +#endif #endif #if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_EMISSIVE) , sampler2D tex_emissive @@ -446,6 +451,9 @@ PBRMix terrain_sample_and_multiply_pbr( #endif #if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL) , tex_vNt +#if TERRAIN_PLANAR_TEXTURE_SAMPLE_COUNT == 3 + , tangent_sign +#endif #endif #if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_EMISSIVE) , tex_emissive diff --git a/indra/newview/app_settings/shaders/class1/deferred/pbrterrainV.glsl b/indra/newview/app_settings/shaders/class1/deferred/pbrterrainV.glsl index f8e826bbdb..c90b2b5926 100644 --- a/indra/newview/app_settings/shaders/class1/deferred/pbrterrainV.glsl +++ b/indra/newview/app_settings/shaders/class1/deferred/pbrterrainV.glsl @@ -43,7 +43,7 @@ out vec3 vary_vertex_normal; // Used by pbrterrainUtilF.glsl out vec3 vary_normal; #if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL) out vec3 vary_tangents[4]; -flat out float vary_sign; +flat out float vary_signs[4]; #endif out vec4 vary_texcoord0; out vec4 vary_texcoord1; @@ -60,7 +60,7 @@ out vec3 vary_position; uniform vec4[5] terrain_texture_transforms; 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); +vec4 terrain_tangent_space_transform(vec4 vertex_tangent, vec3 vertex_normal, vec4[2] khr_gltf_transform); void main() { @@ -75,28 +75,35 @@ void main() #if (TERRAIN_PBR_DETAIL >= TERRAIN_PBR_DETAIL_NORMAL) { vec4[2] ttt; + vec4 transformed_tangent; // 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)); + transformed_tangent = terrain_tangent_space_transform(vec4(t, tangent.w), n, ttt); + vary_tangents[0] = normalize(transformed_tangent.xyz); + vary_signs[0] = transformed_tangent.w; // 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)); + transformed_tangent = terrain_tangent_space_transform(vec4(t, tangent.w), n, ttt); + vary_tangents[1] = normalize(transformed_tangent.xyz); + vary_signs[1] = transformed_tangent.w; // 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)); + transformed_tangent = terrain_tangent_space_transform(vec4(t, tangent.w), n, ttt); + vary_tangents[2] = normalize(transformed_tangent.xyz); + vary_signs[2] = transformed_tangent.w; // 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)); + transformed_tangent = terrain_tangent_space_transform(vec4(t, tangent.w), n, ttt); + vary_tangents[3] = normalize(transformed_tangent.xyz); + vary_signs[3] = transformed_tangent.w; } - - vary_sign = tangent.w; #endif vary_normal = normalize(n); diff --git a/indra/newview/app_settings/shaders/class1/deferred/textureUtilV.glsl b/indra/newview/app_settings/shaders/class1/deferred/textureUtilV.glsl index 767416d564..c75a0e0d5d 100644 --- a/indra/newview/app_settings/shaders/class1/deferred/textureUtilV.glsl +++ b/indra/newview/app_settings/shaders/class1/deferred/textureUtilV.glsl @@ -94,36 +94,48 @@ vec2 terrain_texture_transform(vec2 vertex_texcoord, vec4[2] khr_gltf_transform) // 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. +// In practice, this applies the inverse of the texture transform to the tangent. +// It is effectively an inverse of the rotation // *HACK: Assume the imported GLTF model did not have both normal texture // transforms and tangent vertices. The use of this function is inconsistent // with the GLTF sample viewer when that is the case. See getNormalInfo in // https://raw.githubusercontent.com/KhronosGroup/glTF-Sample-Viewer/47a191931461a6f2e14de48d6da0f0eb6ec2d147/source/Renderer/shaders/material_info.glsl // We may want to account for this case during GLTF model import. // -Cosmic,2023-06-06 -vec3 tangent_space_transform(vec4 vertex_tangent, vec3 vertex_normal, vec4[2] khr_gltf_transform, mat4 sl_animation_transform) +vec4 tangent_space_transform(vec4 vertex_tangent, vec3 vertex_normal, vec4[2] khr_gltf_transform, mat4 sl_animation_transform) { - vec2 weights = vec2(0, 1); - - // Apply texture animation first to avoid shearing and other artifacts (rotation only) - mat2 sl_rot_scale; - sl_rot_scale[0][0] = sl_animation_transform[0][0]; - sl_rot_scale[0][1] = sl_animation_transform[0][1]; - sl_rot_scale[1][0] = sl_animation_transform[1][0]; - sl_rot_scale[1][1] = sl_animation_transform[1][1]; - weights = sl_rot_scale * weights; - // Remove scale - weights = normalize(weights); - - // Convert to left-handed coordinate system - weights.y = -weights.y; + // Immediately convert to left-handed coordinate system, but it has no + // effect here because y is 0 ((1,0) -> (1,0)) + vec2 weights = vec2(1, 0); - // Apply KHR_texture_transform (rotation only) - float khr_rotation = khr_gltf_transform[0].z; + // Apply inverse KHR_texture_transform (rotation and scale sign 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; + vec2 khr_scale_sign = sign(khr_gltf_transform[0].xy); + weights *= khr_scale_sign.xy; + + // *NOTE: Delay conversion to right-handed coordinate system here, to + // remove the need for computing the inverse of the SL texture animation + // matrix. + + // Apply texture animation last to avoid shearing and other artifacts (rotation only) + mat2 inv_sl_rot_scale; + inv_sl_rot_scale[0][0] = sl_animation_transform[0][0]; + inv_sl_rot_scale[0][1] = sl_animation_transform[0][1]; + inv_sl_rot_scale[1][0] = sl_animation_transform[1][0]; + inv_sl_rot_scale[1][1] = sl_animation_transform[1][1]; + weights = inv_sl_rot_scale * weights; + // *NOTE: Scale to be removed later + + // Set weights to default if 0 for some reason + weights.x += 1.0 - abs(sign(sign(weights.x) + (0.5 * sign(weights.y)))); + + // Remove scale from SL texture animation transform + weights = normalize(weights); // Convert back to right-handed coordinate system weights.y = -weights.y; @@ -132,27 +144,41 @@ vec3 tangent_space_transform(vec4 vertex_tangent, vec3 vertex_normal, vec4[2] kh // from the normal and tangent, as seen in the fragment shader vec3 vertex_binormal = vertex_tangent.w * cross(vertex_normal, vertex_tangent.xyz); - return (weights.x * vertex_binormal.xyz) + (weights.y * vertex_tangent.xyz); + // An additional sign flip prevents the binormal from being flipped as a + // result of a propagation of the tangent sign during the cross product. + float sign_flip = khr_scale_sign.x * khr_scale_sign.y; + return vec4((weights.x * vertex_tangent.xyz) + (weights.y * vertex_binormal.xyz), vertex_tangent.w * sign_flip); } // Similar to tangent_space_transform but no texture animation support. -vec3 terrain_tangent_space_transform(vec4 vertex_tangent, vec3 vertex_normal, vec4[2] khr_gltf_transform) +vec4 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); + // Immediately convert to left-handed coordinate system, but it has no + // effect here because y is 0 ((1,0) -> (1,0)) + vec2 weights = vec2(1, 0); - // Apply KHR_texture_transform (rotation only) - float khr_rotation = khr_gltf_transform[0].z; + // Apply inverse KHR_texture_transform (rotation and scale sign 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; + vec2 khr_scale_sign = sign(khr_gltf_transform[0].xy); + weights *= khr_scale_sign.xy; + + // Set weights to default if 0 for some reason + weights.x += 1.0 - abs(sign(sign(weights.x) + (0.5 * sign(weights.y)))); // Convert back to right-handed coordinate system weights.y = -weights.y; + // Similar to the MikkTSpace-compatible method of extracting the binormal + // from the normal and tangent, as seen in the fragment shader vec3 vertex_binormal = vertex_tangent.w * cross(vertex_normal, vertex_tangent.xyz); - return (weights.x * vertex_binormal.xyz) + (weights.y * vertex_tangent.xyz); + // An additional sign flip prevents the binormal from being flipped as a + // result of a propagation of the tangent sign during the cross product. + float sign_flip = khr_scale_sign.x * khr_scale_sign.y; + return vec4((weights.x * vertex_tangent.xyz) + (weights.y * vertex_binormal.xyz), vertex_tangent.w * sign_flip); } -- cgit v1.2.3