DRTVWR-592: (WIP) Roughly working draft of PBR terrain

4 files changed, 20 insertions, 13 deletions

diff --git a/indra/newview/app_settings/shaders/class1/deferred/pbrterrainF.glsl b/indra/newview/app_settings/shaders/class1/deferred/pbrterrainF.glsl
index 60e5776bc6..4de6b9609c 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/pbrterrainF.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/pbrterrainF.glsl
@@ -97,10 +97,11 @@ vec4 sample_and_mix_color4(float alpha1, float alpha2, float alphaFinal, vec2 te
     samples[1] = texture2D(tex1, texcoord);
     samples[2] = texture2D(tex2, texcoord);
     samples[3] = texture2D(tex3, texcoord);
-    samples[0].xyz = srgb_to_linear(samples[0].xyz);
-    samples[1].xyz = srgb_to_linear(samples[1].xyz);
-    samples[2].xyz = srgb_to_linear(samples[2].xyz);
-    samples[3].xyz = srgb_to_linear(samples[3].xyz);
+    // TODO: Why is this needed for pbropaqueF but not here? (and is there different behavior with base color vs emissive color, that also needs to be corrected?)
+    //samples[0].xyz = srgb_to_linear(samples[0].xyz);
+    //samples[1].xyz = srgb_to_linear(samples[1].xyz);
+    //samples[2].xyz = srgb_to_linear(samples[2].xyz);
+    //samples[3].xyz = srgb_to_linear(samples[3].xyz);
     return terrain_mix(samples, alpha1, alpha2, alphaFinal);
 }
 
@@ -116,20 +117,23 @@ vec4 sample_and_mix_vector(float alpha1, float alpha2, float alphaFinal, vec2 te
 
 void main()
 {
+    // Adjust the texture repeats for a more sensible default.
+    float texture_density_factor = 2.0;
+    vec2 terrain_texcoord = texture_density_factor * vary_texcoord0.xy;
     float alpha1 = texture2D(alpha_ramp, vary_texcoord0.zw).a;
     float alpha2 = texture2D(alpha_ramp,vary_texcoord1.xy).a;
     float alphaFinal = texture2D(alpha_ramp, vary_texcoord1.zw).a;
 
-    vec4 base_color = sample_and_mix_color4(alpha1, alpha2, alphaFinal, vary_texcoord0.xy, detail_0_base_color, detail_1_base_color, detail_2_base_color, detail_3_base_color);
+    vec4 base_color = sample_and_mix_color4(alpha1, alpha2, alphaFinal, terrain_texcoord, detail_0_base_color, detail_1_base_color, detail_2_base_color, detail_3_base_color);
     float minimum_alpha = terrain_mix(minimum_alphas, alpha1, alpha2, alphaFinal);
     if (base_color.a < minimum_alpha)
     {
         discard;
     }
 
-    vec4 normal_texture = sample_and_mix_vector(alpha1, alpha2, alphaFinal, vary_texcoord0.xy, detail_0_normal, detail_1_normal, detail_2_normal, detail_3_normal);
-    vec4 metallic_roughness = sample_and_mix_vector(alpha1, alpha2, alphaFinal, vary_texcoord0.xy, detail_0_metallic_roughness, detail_1_metallic_roughness, detail_2_metallic_roughness, detail_3_metallic_roughness);
-    vec3 emissive_texture = sample_and_mix_color3(alpha1, alpha2, alphaFinal, vary_texcoord0.xy, detail_0_emissive, detail_1_emissive, detail_2_emissive, detail_3_emissive);
+    vec4 normal_texture = sample_and_mix_vector(alpha1, alpha2, alphaFinal, terrain_texcoord, detail_0_normal, detail_1_normal, detail_2_normal, detail_3_normal);
+    vec4 metallic_roughness = sample_and_mix_vector(alpha1, alpha2, alphaFinal, terrain_texcoord, detail_0_metallic_roughness, detail_1_metallic_roughness, detail_2_metallic_roughness, detail_3_metallic_roughness);
+    vec3 emissive_texture = sample_and_mix_color3(alpha1, alpha2, alphaFinal, terrain_texcoord, detail_0_emissive, detail_1_emissive, detail_2_emissive, detail_3_emissive);
 
     vec4 baseColorFactor = terrain_mix(baseColorFactors, alpha1, alpha2, alphaFinal);
     float metallicFactor = terrain_mix(metallicFactors, alpha1, alpha2, alphaFinal);
diff --git a/indra/newview/lldrawpoolterrain.cpp b/indra/newview/lldrawpoolterrain.cpp
index 2a0a7bad1c..204fbc56fd 100644
--- a/indra/newview/lldrawpoolterrain.cpp
+++ b/indra/newview/lldrawpoolterrain.cpp
@@ -370,6 +370,7 @@ void LLDrawPoolTerrain::renderFullShaderTextures()
 	gGL.getTexUnit(detail0)->activate();
 }
 
+// TODO: Investigate use of bindFast for PBR terrain textures
 void LLDrawPoolTerrain::renderFullShaderPBR()
 {
 	// Hack! Get the region that this draw pool is rendering from!
@@ -386,7 +387,7 @@ void LLDrawPoolTerrain::renderFullShaderPBR()
 	tp0.setVec(sDetailScale, 0.0f, 0.0f, offset_x);
 	tp1.setVec(0.0f, sDetailScale, 0.0f, offset_y);
 
-    constexpr U32 terrain_material_count = LLViewerShaderMgr::TERRAIN_DETAIL3_BASE_COLOR - LLViewerShaderMgr::TERRAIN_DETAIL0_BASE_COLOR;
+    constexpr U32 terrain_material_count = 1 + LLViewerShaderMgr::TERRAIN_DETAIL3_BASE_COLOR - LLViewerShaderMgr::TERRAIN_DETAIL0_BASE_COLOR;
     S32 detail_basecolor[terrain_material_count];
     S32 detail_normal[terrain_material_count];
     S32 detail_metalrough[terrain_material_count];
@@ -456,12 +457,14 @@ void LLDrawPoolTerrain::renderFullShaderPBR()
         // mAlphaCutoff is only valid for LLGLTFMaterial::ALPHA_MODE_MASK
         // Use 0 here due to GLTF terrain blending (LLGLTFMaterial::bind uses
         // -1 for easier debugging)
-        F32 min_alpha = 0.f;
+        F32 min_alpha = -0.0f;
         if (material->mAlphaMode == LLGLTFMaterial::ALPHA_MODE_MASK)
         {
-            min_alpha = material->mAlphaCutoff;
+            // dividing the alpha cutoff by transparency here allows the shader to compare against
+            // the alpha value of the texture without needing the transparency value
+            min_alpha = material->mAlphaCutoff/material->mBaseColor.mV[3];
         }
-
+        minimum_alphas[i] = min_alpha;
     }
     shader->uniform4fv(LLShaderMgr::TERRAIN_BASE_COLOR_FACTORS, terrain_material_count, (F32*)base_color_factors);
     shader->uniform4f(LLShaderMgr::TERRAIN_METALLIC_FACTORS, metallic_factors[0], metallic_factors[1], metallic_factors[2], metallic_factors[3]);
diff --git a/indra/newview/llfloaterregioninfo.cpp b/indra/newview/llfloaterregioninfo.cpp
index b5698c1d65..2635ac3a71 100644
--- a/indra/newview/llfloaterregioninfo.cpp
+++ b/indra/newview/llfloaterregioninfo.cpp
@@ -1531,7 +1531,6 @@ bool LLPanelRegionTerrainInfo::refreshFromRegion(LLViewerRegion* region)
 		LLVLComposition* compp = region->getComposition();
 
         // Are these 4 texture IDs or 4 material IDs? Who knows! Let's set the IDs on both pickers for now.
-        // *TODO: Determine the asset type of IDs, to determine which editing mode to display.
 		LLTextureCtrl* asset_ctrl;
 		std::string buffer;
 		for(S32 i = 0; i < TERRAIN_TEXTURE_COUNT; ++i)
diff --git a/indra/newview/llvlcomposition.cpp b/indra/newview/llvlcomposition.cpp
index 5d711f4e5d..815489f753 100644
--- a/indra/newview/llvlcomposition.cpp
+++ b/indra/newview/llvlcomposition.cpp
@@ -360,6 +360,7 @@ BOOL LLVLComposition::generateComposition()
     return FALSE;
 }
 
+// TODO: Re-evaluate usefulness of this function in the PBR case. There is currently a hack here to treat the material base color like a legacy terrain texture, but I'm not sure if that's useful.
 BOOL LLVLComposition::generateTexture(const F32 x, const F32 y,
 									  const F32 width, const F32 height)
 {