Clouds curl texture

internal/AtmosphereRef.cpp

@@ -7,6 +7,7 @@
 namespace Ray {
 #include "precomputed/__3d_noise_tex.inl"
 #include "precomputed/__cirrus_tex.inl"
+#include "precomputed/__curl_tex.inl"
 #include "precomputed/__moon_tex.inl"
 #include "precomputed/__weather_tex.inl"
 
@@ -284,6 +285,26 @@ float Sample3dNoiseTex(fvec4 uvw) {
     return ((1.0f - k.get<2>()) * n0xx + k.get<2>() * n1xx) / 255.0f;
 }
 
+force_inline fvec4 FetchCurlTex(const int x, const int y) {
+    return fvec4{float(__curl_tex[3 * (y * CURL_TEX_RES + x) + 0]), float(__curl_tex[3 * (y * CURL_TEX_RES + x) + 1]),
+                 float(__curl_tex[3 * (y * CURL_TEX_RES + x) + 2]), 0.0f};
+}
+
+fvec4 SampleCurlTex(fvec4 uv) {
+    uv = fract(uv - 0.5f / CURL_TEX_RES) * fvec4(CURL_TEX_RES);
+    auto iuv0 = ivec4{uv};
+    iuv0 = clamp(iuv0, ivec4{0}, ivec4{CURL_TEX_RES - 1, CURL_TEX_RES - 1, 0, 0});
+    const ivec4 iuv1 = (iuv0 + 1) & ivec4{CURL_TEX_RES - 1, CURL_TEX_RES - 1, 0, 0};
+
+    const fvec4 m00 = FetchCurlTex(iuv0.get<0>(), iuv0.get<1>()), m01 = FetchCurlTex(iuv1.get<0>(), iuv0.get<1>()),
+                m10 = FetchCurlTex(iuv0.get<0>(), iuv1.get<1>()), m11 = FetchCurlTex(iuv1.get<0>(), iuv1.get<1>());
+
+    const fvec4 k = fract(uv);
+    const fvec4 m0 = m01 * k.get<0>() + m00 * (1.0f - k.get<0>()), m1 = m11 * k.get<0>() + m10 * (1.0f - k.get<0>());
+
+    return srgb_to_linear((m1 * k.get<1>() + m0 * (1.0f - k.get<1>())) * (1.0f / 255.0f));
+}
+
 // Taken from https://github.com/armory3d/armory_ci/blob/master/build_untitled/compiled/Shaders/world_pass.frag.glsl
 float GetDensityHeightGradientForPoint(float height, float cloud_type) {
     const auto stratusGrad = fvec4(0.02f, 0.05f, 0.09f, 0.11f);
@@ -321,6 +342,14 @@ float GetCloudsDensity(const atmosphere_params_t &params, fvec4 local_position,
 
     local_position /= 1.5f * (params.clouds_height_end - params.clouds_height_beg);
 
+    // TODO: Apply animated cloud offset here
+    const fvec4 curl_read0 = SampleCurlTex(8.0f * fvec4{local_position.get<0>(), local_position.get<2>(), 0.0f, 0.0f});
+    local_position += curl_read0 * out_height_fraction * 0.25f;
+
+    fvec4 curl_read1 = SampleCurlTex(16.0f * fvec4{local_position.get<1>(), local_position.get<0>(), 0.0f, 0.0f});
+    curl_read1 = fvec4{curl_read1.get<1>(), curl_read1.get<2>(), curl_read1.get<0>(), 0.0f};
+    local_position += curl_read1 * (1.0f - out_height_fraction) * 0.05f;
+
     const float noise_read = Sample3dNoiseTex(local_position);
     return 3.0f * Ray::mix(fmaxf(0.0f, 1.0f - cloud_type * 2.0f), 1.0f, out_height_fraction) *
            remap(cloud_coverage, 0.6f * noise_read);
@@ -398,7 +427,6 @@ fvec4 SampleMoonTex(fvec4 uv) {
                 m10 = FetchMoonTex(iuv0.get<0>(), iuv1.get<1>()), m11 = FetchMoonTex(iuv1.get<0>(), iuv1.get<1>());
 
     const fvec4 k = fract(uv);
-
     const fvec4 m0 = m01 * k.get<0>() + m00 * (1.0f - k.get<0>()), m1 = m11 * k.get<0>() + m10 * (1.0f - k.get<0>());
 
     return srgb_to_linear((m1 * k.get<1>() + m0 * (1.0f - k.get<1>())) * (1.0f / 255.0f));
@@ -419,7 +447,6 @@ fvec4 SampleCirrusTex(fvec4 uv) {
                 m10 = FetchCirrusTex(iuv0.get<0>(), iuv1.get<1>()), m11 = FetchCirrusTex(iuv1.get<0>(), iuv1.get<1>());
 
     const fvec4 k = fract(uv);
-
     const fvec4 m0 = m01 * k.get<0>() + m00 * (1.0f - k.get<0>()), m1 = m11 * k.get<0>() + m10 * (1.0f - k.get<0>());
 
     return srgb_to_linear((m1 * k.get<1>() + m0 * (1.0f - k.get<1>())) * (1.0f / 255.0f));

internal/Constants.inl

@@ -142,7 +142,7 @@ const int SKY_TRANSMITTANCE_LUT_H = 64;
 const int SKY_MULTISCATTER_LUT_RES = 32;
 const int SKY_PRE_ATMOSPHERE_SAMPLE_COUNT = 4;
 const int SKY_MAIN_ATMOSPHERE_SAMPLE_COUNT = 12;
-const int SKY_CLOUDS_SAMPLE_COUNT = 32;
+const int SKY_CLOUDS_SAMPLE_COUNT = 48;
 const float SKY_CLOUDS_HORIZON_CUTOFF = 0.005f;
 const float SKY_MOON_SUN_RELATION = 0.0000001f;
 const float SKY_STARS_THRESHOLD = 14.0f;

internal/RendererDX.cpp

@@ -698,6 +698,7 @@ void Ray::Dx::Renderer::RenderScene(const SceneBase &scene, RegionContext &regio
                                   s.sky_moon_tex_,
                                   s.sky_weather_tex_,
                                   s.sky_cirrus_tex_,
+                                  s.sky_curl_tex_,
                                   s.sky_noise3d_tex_};
 
     TransitionSceneResources(cmd_buf, sc_data);
@@ -1406,6 +1407,7 @@ void Ray::Dx::Renderer::UpdateSpatialCache(const SceneBase &scene, RegionContext
                                   {},
                                   {},
                                   {},
+                                  {},
                                   {}};
 
 #if !RUN_IN_LOCKSTEP

internal/RendererGPU.h

@@ -39,6 +39,7 @@ struct scene_data_t {
     const Texture2D &moon_tex;
     const Texture2D &weather_tex;
     const Texture2D &cirrus_tex;
+    const Texture2D &curl_tex;
     const Texture3D &noise3d_tex;
 };
 

internal/RendererGPU_kernels.h

@@ -838,6 +838,7 @@ inline void Ray::NS::Renderer::kernel_ShadeSky(CommandBuffer cmd_buf, const pass
         {eBindTarget::Tex2DSampled, ShadeSky::MOON_TEX_SLOT, sc_data.moon_tex},
         {eBindTarget::Tex2DSampled, ShadeSky::WEATHER_TEX_SLOT, sc_data.weather_tex},
         {eBindTarget::Tex2DSampled, ShadeSky::CIRRUS_TEX_SLOT, sc_data.cirrus_tex},
+        {eBindTarget::Tex2DSampled, ShadeSky::CURL_TEX_SLOT, sc_data.curl_tex},
         {eBindTarget::Tex3DSampled, ShadeSky::NOISE3D_TEX_SLOT, sc_data.noise3d_tex},
         {eBindTarget::Image, ShadeSky::OUT_IMG_SLOT, out_img}};
 

internal/RendererVK.cpp

@@ -712,6 +712,7 @@ void Ray::Vk::Renderer::RenderScene(const SceneBase &scene, RegionContext &regio
                                   s.sky_moon_tex_,
                                   s.sky_weather_tex_,
                                   s.sky_cirrus_tex_,
+                                  s.sky_curl_tex_,
                                   s.sky_noise3d_tex_};
     TransitionSceneResources(cmd_buf, sc_data);
 
@@ -1450,6 +1451,7 @@ void Ray::Vk::Renderer::UpdateSpatialCache(const SceneBase &scene, RegionContext
                                   {},
                                   {},
                                   {},
+                                  {},
                                   {}};
 
 #if !RUN_IN_LOCKSTEP

internal/SceneGPU.h

@@ -22,6 +22,8 @@ extern const int NOISE_3D_RES;
 extern const uint8_t __3d_noise_tex[];
 extern const int CIRRUS_TEX_RES;
 extern const uint8_t __cirrus_tex[];
+extern const int CURL_TEX_RES;
+extern const uint8_t __curl_tex[];
 
 Ref::fvec4 rgb_to_rgbe(const Ref::fvec4 &rgb);
 namespace NS {
@@ -82,7 +84,7 @@ class Scene : public SceneCommon {
     std::vector<uint32_t> dir_lights_; // compacted list of all directional lights
 
     Texture2D sky_transmittance_lut_tex_, sky_multiscatter_lut_tex_;
-    Texture2D sky_moon_tex_, sky_weather_tex_, sky_cirrus_tex_;
+    Texture2D sky_moon_tex_, sky_weather_tex_, sky_cirrus_tex_, sky_curl_tex_;
     Texture3D sky_noise3d_tex_;
 
     LightHandle env_map_light_ = InvalidLightHandle;
@@ -1598,7 +1600,7 @@ inline void Ray::NS::Scene::Rebuild_SWRT_TLAS_nolock() {
     tlas_root_node_ = bvh_nodes[0];
 }
 
-//#define DUMP_SKY_ENV
+// #define DUMP_SKY_ENV
 #ifdef DUMP_SKY_ENV
 extern "C" {
 int SaveEXR(const float *data, int width, int height, int components, const int save_as_fp16, const char *outfilename,
@@ -1642,6 +1644,7 @@ inline std::vector<Ray::color_rgba8_t> Ray::NS::Scene::CalcSkyEnvTexture(const a
             {eBindTarget::Tex2DSampled, ShadeSky::MOON_TEX_SLOT, sky_moon_tex_},
             {eBindTarget::Tex2DSampled, ShadeSky::WEATHER_TEX_SLOT, sky_weather_tex_},
             {eBindTarget::Tex2DSampled, ShadeSky::CIRRUS_TEX_SLOT, sky_cirrus_tex_},
+            {eBindTarget::Tex2DSampled, ShadeSky::CURL_TEX_SLOT, sky_curl_tex_},
             {eBindTarget::Tex3DSampled, ShadeSky::NOISE3D_TEX_SLOT, sky_noise3d_tex_},
             {eBindTarget::Image, ShadeSky::OUT_IMG_SLOT, temp_img}};
 
@@ -1831,6 +1834,35 @@ Ray::NS::Scene::PrepareSkyEnvMap_nolock(const std::function<void(int, int, Paral
         stage_buf.FreeImmediate();
     }
 
+    if (!sky_curl_tex_.ready()) {
+        Tex2DParams params;
+        params.w = params.h = CURL_TEX_RES;
+        params.format = eTexFormat::RawRGBA8888;
+        params.flags = eTexFlags::SRGB;
+        params.usage = eTexUsageBits::Sampled | eTexUsageBits::Transfer;
+        params.sampling.filter = eTexFilter::BilinearNoMipmap;
+        params.sampling.wrap = eTexWrap::Repeat;
+
+        sky_curl_tex_ = Texture2D{"Curl Tex", ctx_, params, ctx_->default_memory_allocs(), log_};
+
+        Buffer stage_buf = Buffer("Temp stage buf", ctx_, eBufType::Upload, 4 * CURL_TEX_RES * CURL_TEX_RES);
+        uint8_t *mapped_ptr = stage_buf.Map();
+        for (int i = 0; i < CURL_TEX_RES * CURL_TEX_RES; ++i) {
+            mapped_ptr[4 * i + 0] = __curl_tex[3 * i + 0];
+            mapped_ptr[4 * i + 1] = __curl_tex[3 * i + 1];
+            mapped_ptr[4 * i + 2] = __curl_tex[3 * i + 2];
+            mapped_ptr[4 * i + 3] = 255;
+        }
+        stage_buf.Unmap();
+
+        CommandBuffer cmd_buf = BegSingleTimeCommands(ctx_->api(), ctx_->device(), ctx_->temp_command_pool());
+        sky_curl_tex_.SetSubImage(0, 0, 0, CURL_TEX_RES, CURL_TEX_RES, eTexFormat::RawRGBA8888, stage_buf, cmd_buf, 0,
+                                  stage_buf.size());
+        EndSingleTimeCommands(ctx_->api(), ctx_->device(), ctx_->graphics_queue(), cmd_buf, ctx_->temp_command_pool());
+
+        stage_buf.FreeImmediate();
+    }
+
     if (!sky_noise3d_tex_.handle()) {
         Tex3DParams params;
         params.w = params.h = params.d = NOISE_3D_RES;

internal/shaders/shade_sky.comp.glsl

@@ -40,6 +40,7 @@ layout(binding = MULTISCATTER_LUT_SLOT) uniform sampler2D g_multiscatter_lut;
 layout(binding = MOON_TEX_SLOT) uniform sampler2D g_moon_tex;
 layout(binding = WEATHER_TEX_SLOT) uniform sampler2D g_weather_tex;
 layout(binding = CIRRUS_TEX_SLOT) uniform sampler2D g_cirrus_tex;
+layout(binding = CURL_TEX_SLOT) uniform sampler2D g_curl_tex;
 layout(binding = NOISE3D_TEX_SLOT) uniform sampler3D g_noise3d_tex;
 
 layout(binding = OUT_IMG_SLOT, rgba32f) uniform image2D g_out_img;
@@ -378,6 +379,13 @@ float GetCloudsDensity(vec3 local_position, out float out_local_height, out floa
 
     local_position /= 1.5 * (g_atmosphere_params.clouds_height_end - g_atmosphere_params.clouds_height_beg);
 
+    // TODO: Apply animated cloud offset here
+    const vec3 curl_read0 = textureLod(g_curl_tex, 8.0 * local_position.xz, 0.0).xyz;
+    local_position += curl_read0 * out_height_fraction * 0.25;
+
+    const vec3 curl_read1 = textureLod(g_curl_tex, 16.0 * local_position.yx, 0.0).yzx;
+    local_position += curl_read1 * (1.0 - out_height_fraction) * 0.05;
+
     const float noise_read = textureLod(g_noise3d_tex, local_position, 0.0).x;
     return 3.0 * mix(max(0.0, 1.0 - cloud_type * 2.0), 1.0, out_height_fraction) *
            remap(cloud_coverage, 0.6 * noise_read);

internal/shaders/shade_sky_interface.h

@@ -40,7 +40,8 @@ const int MULTISCATTER_LUT_SLOT = 10;
 const int MOON_TEX_SLOT = 11;
 const int WEATHER_TEX_SLOT = 12;
 const int CIRRUS_TEX_SLOT = 13;
-const int NOISE3D_TEX_SLOT = 14;
+const int CURL_TEX_SLOT = 14;
+const int NOISE3D_TEX_SLOT = 15;
 
 const int OUT_IMG_SLOT = 0;
 

tests/test_materials.cpp

@@ -1625,7 +1625,7 @@ void test_complex_mat5_dir_light(const char *arch_list[], const char *preferred_
 }
 
 void test_complex_mat5_sun_light(const char *arch_list[], const char *preferred_device) {
-    const int SampleCount = 13;
+    const int SampleCount = 14;
     const double MinPSNR = 24.05;
     const int PixThres = 5219;
 
@@ -1646,7 +1646,7 @@ void test_complex_mat5_sun_light(const char *arch_list[], const char *preferred_
 }
 
 void test_complex_mat5_moon_light(const char *arch_list[], const char *preferred_device) {
-    const int SampleCount = 12;
+    const int SampleCount = 14;
     const int PixThres = 370;
 
     Ray::principled_mat_desc_t metal_mat_desc;