EEVEE-Next: Reduce image bindings.

This change combines the diffuse/specular light passes into a single texture
array, freeing up an image binding for cryptomatte.

When diffuse/specular light pass and/or requested a
texture array will be allocated. Only when specular light is requested 2 images will always be allocated. This increases the
memory overhead when viewing the specular light renderpass in the viewport. For final rendering it is a common scenario that none
or both are requested.

Reviewed By: fclem

Differential Revision: https://developer.blender.org/D15701

source/blender/draw/engines/eevee_next/eevee_film.cc

@@ -389,9 +389,8 @@ void Film::sync()
   DRW_shgroup_uniform_texture_ref(grp, "combined_tx", &combined_final_tx_);
   DRW_shgroup_uniform_texture_ref(grp, "normal_tx", &rbuffers.normal_tx);
   DRW_shgroup_uniform_texture_ref(grp, "vector_tx", &rbuffers.vector_tx);
-  DRW_shgroup_uniform_texture_ref(grp, "diffuse_light_tx", &rbuffers.diffuse_light_tx);
+  DRW_shgroup_uniform_texture_ref(grp, "light_tx", &rbuffers.light_tx);
   DRW_shgroup_uniform_texture_ref(grp, "diffuse_color_tx", &rbuffers.diffuse_color_tx);
-  DRW_shgroup_uniform_texture_ref(grp, "specular_light_tx", &rbuffers.specular_light_tx);
   DRW_shgroup_uniform_texture_ref(grp, "specular_color_tx", &rbuffers.specular_color_tx);
   DRW_shgroup_uniform_texture_ref(grp, "volume_light_tx", &rbuffers.volume_light_tx);
   DRW_shgroup_uniform_texture_ref(grp, "emission_tx", &rbuffers.emission_tx);

source/blender/draw/engines/eevee_next/eevee_pipeline.cc

@@ -43,9 +43,8 @@ void WorldPipeline::sync(GPUMaterial *gpumat)
   DRW_shgroup_storage_block_ref(grp, "aov_buf", &inst_.film.aovs_info);
   /* RenderPasses. Cleared by background (even if bad practice). */
   DRW_shgroup_uniform_image_ref(grp, "rp_normal_img", &rbufs.normal_tx);
-  DRW_shgroup_uniform_image_ref(grp, "rp_diffuse_light_img", &rbufs.diffuse_light_tx);
+  DRW_shgroup_uniform_image_ref(grp, "rp_light_img", &rbufs.light_tx);
   DRW_shgroup_uniform_image_ref(grp, "rp_diffuse_color_img", &rbufs.diffuse_color_tx);
-  DRW_shgroup_uniform_image_ref(grp, "rp_specular_light_img", &rbufs.specular_light_tx);
   DRW_shgroup_uniform_image_ref(grp, "rp_specular_color_img", &rbufs.specular_color_tx);
   DRW_shgroup_uniform_image_ref(grp, "rp_emission_img", &rbufs.emission_tx);
   /* To allow opaque pass rendering over it. */
@@ -122,9 +121,8 @@ DRWShadingGroup *ForwardPipeline::material_opaque_add(::Material *blender_mat, G
   DRW_shgroup_storage_block_ref(grp, "aov_buf", &inst_.film.aovs_info);
   /* RenderPasses. */
   DRW_shgroup_uniform_image_ref(grp, "rp_normal_img", &rbufs.normal_tx);
-  DRW_shgroup_uniform_image_ref(grp, "rp_diffuse_light_img", &rbufs.diffuse_light_tx);
+  DRW_shgroup_uniform_image_ref(grp, "rp_light_img", &rbufs.light_tx);
   DRW_shgroup_uniform_image_ref(grp, "rp_diffuse_color_img", &rbufs.diffuse_color_tx);
-  DRW_shgroup_uniform_image_ref(grp, "rp_specular_light_img", &rbufs.specular_light_tx);
   DRW_shgroup_uniform_image_ref(grp, "rp_specular_color_img", &rbufs.specular_color_tx);
   DRW_shgroup_uniform_image_ref(grp, "rp_emission_img", &rbufs.emission_tx);
 
@@ -206,9 +204,8 @@ DRWShadingGroup *ForwardPipeline::material_transparent_add(::Material *blender_m
     DRW_shgroup_storage_block_ref(grp, "aov_buf", &inst_.film.aovs_info);
     /* RenderPasses. */
     DRW_shgroup_uniform_image_ref(grp, "rp_normal_img", &rbufs.normal_tx);
-    DRW_shgroup_uniform_image_ref(grp, "rp_diffuse_light_img", &rbufs.diffuse_light_tx);
+    DRW_shgroup_uniform_image_ref(grp, "rp_light_img", &rbufs.light_tx);
     DRW_shgroup_uniform_image_ref(grp, "rp_diffuse_color_img", &rbufs.diffuse_color_tx);
-    DRW_shgroup_uniform_image_ref(grp, "rp_specular_light_img", &rbufs.specular_light_tx);
     DRW_shgroup_uniform_image_ref(grp, "rp_specular_color_img", &rbufs.specular_color_tx);
     DRW_shgroup_uniform_image_ref(grp, "rp_emission_img", &rbufs.emission_tx);
   }

source/blender/draw/engines/eevee_next/eevee_renderbuffers.cc

@@ -26,9 +26,11 @@ namespace blender::eevee {
 
 void RenderBuffers::acquire(int2 extent)
 {
+  const eViewLayerEEVEEPassType enabled_passes = inst_.film.enabled_passes_get();
+
   auto pass_extent = [&](eViewLayerEEVEEPassType pass_bit) -> int2 {
     /* Use dummy texture for disabled passes. Allows correct bindings. */
-    return (inst_.film.enabled_passes_get() & pass_bit) ? extent : int2(1);
+    return (enabled_passes & pass_bit) ? extent : int2(1);
   };
 
   eGPUTextureFormat color_format = GPU_RGBA16F;
@@ -38,17 +40,22 @@ void RenderBuffers::acquire(int2 extent)
   depth_tx.acquire(extent, GPU_DEPTH24_STENCIL8);
   combined_tx.acquire(extent, color_format);
 
-  bool do_vector_render_pass = (inst_.film.enabled_passes_get() & EEVEE_RENDER_PASS_VECTOR) ||
+  bool do_vector_render_pass = (enabled_passes & EEVEE_RENDER_PASS_VECTOR) ||
                                (inst_.motion_blur.postfx_enabled() && !inst_.is_viewport());
+  uint32_t max_light_color_layer = max_ii(enabled_passes & EEVEE_RENDER_PASS_DIFFUSE_LIGHT ?
+                                              RENDER_PASS_LAYER_DIFFUSE_LIGHT :
+                                              -1,
+                                          enabled_passes & EEVEE_RENDER_PASS_SPECULAR_LIGHT ?
+                                              RENDER_PASS_LAYER_SPECULAR_LIGHT :
+                                              -1) +
+                                   1;
   /* Only RG16F when only doing only reprojection or motion blur. */
   eGPUTextureFormat vector_format = do_vector_render_pass ? GPU_RGBA16F : GPU_RG16F;
   /* TODO(fclem): Make vector pass allocation optional if no TAA or motion blur is needed. */
   vector_tx.acquire(extent, vector_format);
 
   normal_tx.acquire(pass_extent(EEVEE_RENDER_PASS_NORMAL), color_format);
-  diffuse_light_tx.acquire(pass_extent(EEVEE_RENDER_PASS_DIFFUSE_LIGHT), color_format);
   diffuse_color_tx.acquire(pass_extent(EEVEE_RENDER_PASS_DIFFUSE_COLOR), color_format);
-  specular_light_tx.acquire(pass_extent(EEVEE_RENDER_PASS_SPECULAR_LIGHT), color_format);
   specular_color_tx.acquire(pass_extent(EEVEE_RENDER_PASS_SPECULAR_COLOR), color_format);
   volume_light_tx.acquire(pass_extent(EEVEE_RENDER_PASS_VOLUME_LIGHT), color_format);
   emission_tx.acquire(pass_extent(EEVEE_RENDER_PASS_EMIT), color_format);
@@ -56,6 +63,10 @@ void RenderBuffers::acquire(int2 extent)
   shadow_tx.acquire(pass_extent(EEVEE_RENDER_PASS_SHADOW), float_format);
   ambient_occlusion_tx.acquire(pass_extent(EEVEE_RENDER_PASS_AO), float_format);
 
+  light_tx.ensure_2d_array(color_format,
+                           max_light_color_layer > 0 ? extent : int2(1),
+                           max_ii(1, max_light_color_layer));
+
   const AOVsInfoData &aovs = inst_.film.aovs_info;
   aov_color_tx.ensure_2d_array(
       color_format, (aovs.color_len > 0) ? extent : int2(1), max_ii(1, aovs.color_len));
@@ -70,9 +81,7 @@ void RenderBuffers::release()
 
   normal_tx.release();
   vector_tx.release();
-  diffuse_light_tx.release();
   diffuse_color_tx.release();
-  specular_light_tx.release();
   specular_color_tx.release();
   volume_light_tx.release();
   emission_tx.release();

source/blender/draw/engines/eevee_next/eevee_renderbuffers.hh

@@ -28,9 +28,7 @@ class RenderBuffers {
   // TextureFromPool mist_tx; /* Derived from depth_tx during accumulation. */
   TextureFromPool normal_tx;
   TextureFromPool vector_tx;
-  TextureFromPool diffuse_light_tx;
   TextureFromPool diffuse_color_tx;
-  TextureFromPool specular_light_tx;
   TextureFromPool specular_color_tx;
   TextureFromPool volume_light_tx;
   TextureFromPool emission_tx;
@@ -39,6 +37,7 @@ class RenderBuffers {
   TextureFromPool ambient_occlusion_tx;
   // TextureFromPool cryptomatte_tx; /* TODO */
   /* TODO(fclem): Use texture from pool once they support texture array. */
+  Texture light_tx;
   Texture aov_color_tx;
   Texture aov_value_tx;
 

source/blender/draw/engines/eevee_next/eevee_shader_shared.hh

@@ -291,6 +291,17 @@ static inline float film_filter_weight(float filter_radius, float sample_distanc
 
 /** \} */
 
+/* -------------------------------------------------------------------- */
+/** \name Render passes
+ * \{ */
+
+enum eRenderPassLayerIndex : uint32_t {
+  RENDER_PASS_LAYER_DIFFUSE_LIGHT = 0u,
+  RENDER_PASS_LAYER_SPECULAR_LIGHT = 1u,
+};
+
+/** \} */
+
 /* -------------------------------------------------------------------- */
 /** \name Arbitrary Output Variables
  * \{ */

source/blender/draw/engines/eevee_next/shaders/eevee_film_lib.glsl

@@ -105,12 +105,18 @@ void film_sample_accum(FilmSample samp, int pass_id, sampler2D tex, inout float
   accum += texelFetch(tex, samp.texel, 0).x * samp.weight;
 }
 
-void film_sample_accum(FilmSample samp, int pass_id, sampler2DArray tex, inout vec4 accum)
+void film_sample_accum(
+    FilmSample samp, int pass_id, uint layer, sampler2DArray tex, inout vec4 accum)
 {
   if (pass_id == -1) {
     return;
   }
-  accum += texelFetch(tex, ivec3(samp.texel, pass_id), 0) * samp.weight;
+  accum += texelFetch(tex, ivec3(samp.texel, layer), 0) * samp.weight;
+}
+
+void film_sample_accum(FilmSample samp, int pass_id, sampler2DArray tex, inout vec4 accum)
+{
+  film_sample_accum(samp, pass_id, pass_id, tex, accum);
 }
 
 void film_sample_accum(FilmSample samp, int pass_id, sampler2DArray tex, inout float accum)
@@ -632,8 +638,16 @@ void film_process_data(ivec2 texel_film, out vec4 out_color, out float out_depth
 
     for (int i = 0; i < film_buf.samples_len; i++) {
       FilmSample src = film_sample_get(i, texel_film);
-      film_sample_accum(src, film_buf.diffuse_light_id, diffuse_light_tx, diffuse_light_accum);
+      film_sample_accum(src,
-      film_sample_accum(src, film_buf.specular_light_id, specular_light_tx, specular_light_accum);
+                        film_buf.diffuse_light_id,
+                        RENDER_PASS_LAYER_DIFFUSE_LIGHT,
+                        light_tx,
+                        diffuse_light_accum);
+      film_sample_accum(src,
+                        film_buf.specular_light_id,
+                        RENDER_PASS_LAYER_SPECULAR_LIGHT,
+                        light_tx,
+                        specular_light_accum);
       film_sample_accum(src, film_buf.volume_light_id, volume_light_tx, volume_light_accum);
       film_sample_accum(src, film_buf.emission_id, emission_tx, emission_accum);
     }

source/blender/draw/engines/eevee_next/shaders/eevee_surf_forward_frag.glsl

@@ -99,9 +99,11 @@ void main()
 
   ivec2 out_texel = ivec2(gl_FragCoord.xy);
   imageStore(rp_normal_img, out_texel, vec4(out_normal, 1.0));
-  imageStore(rp_diffuse_light_img, out_texel, vec4(diffuse_light, 1.0));
+  imageStore(
+      rp_light_img, ivec3(out_texel, RENDER_PASS_LAYER_DIFFUSE_LIGHT), vec4(diffuse_light, 1.0));
+  imageStore(
+      rp_light_img, ivec3(out_texel, RENDER_PASS_LAYER_SPECULAR_LIGHT), vec4(specular_light, 1.0));
   imageStore(rp_diffuse_color_img, out_texel, vec4(g_diffuse_data.color, 1.0));
-  imageStore(rp_specular_light_img, out_texel, vec4(specular_light, 1.0));
   imageStore(rp_specular_color_img, out_texel, vec4(specular_color, 1.0));
   imageStore(rp_emission_img, out_texel, vec4(g_emission, 1.0));
 

source/blender/draw/engines/eevee_next/shaders/eevee_surf_world_frag.glsl

@@ -26,9 +26,11 @@ void main()
 
   ivec2 out_texel = ivec2(gl_FragCoord.xy);
   imageStore(rp_normal_img, out_texel, vec4(0.0, 0.0, 0.0, 1.0));
-  imageStore(rp_diffuse_light_img, out_texel, vec4(0.0, 0.0, 0.0, 1.0));
+  imageStore(
+      rp_light_img, ivec3(out_texel, RENDER_PASS_LAYER_DIFFUSE_LIGHT), vec4(0.0, 0.0, 0.0, 1.0));
+  imageStore(
+      rp_light_img, ivec3(out_texel, RENDER_PASS_LAYER_SPECULAR_LIGHT), vec4(0.0, 0.0, 0.0, 1.0));
   imageStore(rp_diffuse_color_img, out_texel, vec4(0.0, 0.0, 0.0, 1.0));
-  imageStore(rp_specular_light_img, out_texel, vec4(0.0, 0.0, 0.0, 1.0));
   imageStore(rp_specular_color_img, out_texel, vec4(0.0, 0.0, 0.0, 1.0));
   imageStore(rp_emission_img, out_texel, vec4(0.0, 0.0, 0.0, 1.0));
 

source/blender/draw/engines/eevee_next/shaders/infos/eevee_film_info.hh

@@ -9,19 +9,18 @@ GPU_SHADER_CREATE_INFO(eevee_film)
     .sampler(1, ImageType::FLOAT_2D, "combined_tx")
     .sampler(2, ImageType::FLOAT_2D, "normal_tx")
     .sampler(3, ImageType::FLOAT_2D, "vector_tx")
-    .sampler(4, ImageType::FLOAT_2D, "diffuse_light_tx")
+    .sampler(4, ImageType::FLOAT_2D_ARRAY, "light_tx")
     .sampler(5, ImageType::FLOAT_2D, "diffuse_color_tx")
-    .sampler(6, ImageType::FLOAT_2D, "specular_light_tx")
+    .sampler(6, ImageType::FLOAT_2D, "specular_color_tx")
-    .sampler(7, ImageType::FLOAT_2D, "specular_color_tx")
+    .sampler(7, ImageType::FLOAT_2D, "volume_light_tx")
-    .sampler(8, ImageType::FLOAT_2D, "volume_light_tx")
+    .sampler(8, ImageType::FLOAT_2D, "emission_tx")
-    .sampler(9, ImageType::FLOAT_2D, "emission_tx")
+    .sampler(9, ImageType::FLOAT_2D, "environment_tx")
-    .sampler(10, ImageType::FLOAT_2D, "environment_tx")
+    .sampler(10, ImageType::FLOAT_2D, "shadow_tx")
-    .sampler(11, ImageType::FLOAT_2D, "shadow_tx")
+    .sampler(11, ImageType::FLOAT_2D, "ambient_occlusion_tx")
-    .sampler(12, ImageType::FLOAT_2D, "ambient_occlusion_tx")
+    .sampler(12, ImageType::FLOAT_2D_ARRAY, "aov_color_tx")
-    .sampler(13, ImageType::FLOAT_2D_ARRAY, "aov_color_tx")
+    .sampler(13, ImageType::FLOAT_2D_ARRAY, "aov_value_tx")
-    .sampler(14, ImageType::FLOAT_2D_ARRAY, "aov_value_tx")
     /* Color History for TAA needs to be sampler to leverage bilinear sampling. */
-    .sampler(15, ImageType::FLOAT_2D, "in_combined_tx")
+    .sampler(14, ImageType::FLOAT_2D, "in_combined_tx")
     // .sampler(15, ImageType::FLOAT_2D, "cryptomatte_tx") /* TODO */
     .image(0, GPU_R32F, Qualifier::READ, ImageType::FLOAT_2D_ARRAY, "in_weight_img")
     .image(1, GPU_R32F, Qualifier::WRITE, ImageType::FLOAT_2D_ARRAY, "out_weight_img")

source/blender/draw/engines/eevee_next/shaders/infos/eevee_material_info.hh

@@ -78,8 +78,8 @@ GPU_SHADER_INTERFACE_INFO(eevee_surf_iface, "interp")
 
 GPU_SHADER_CREATE_INFO(eevee_aov_out)
     .define("MAT_AOV_SUPPORT")
-    .image_array_out(6, Qualifier::WRITE, GPU_RGBA16F, "aov_color_img")
+    .image_array_out(5, Qualifier::WRITE, GPU_RGBA16F, "aov_color_img")
-    .image_array_out(7, Qualifier::WRITE, GPU_R16F, "aov_value_img")
+    .image_array_out(6, Qualifier::WRITE, GPU_R16F, "aov_value_img")
     .storage_buf(7, Qualifier::READ, "AOVsInfoData", "aov_buf");
 
 GPU_SHADER_CREATE_INFO(eevee_surf_deferred)
@@ -113,11 +113,10 @@ GPU_SHADER_CREATE_INFO(eevee_surf_forward)
     .fragment_out(0, Type::VEC4, "out_transmittance", DualBlend::SRC_1)
     .fragment_source("eevee_surf_forward_frag.glsl")
     .image_out(0, Qualifier::READ_WRITE, GPU_RGBA16F, "rp_normal_img")
-    .image_out(1, Qualifier::READ_WRITE, GPU_RGBA16F, "rp_diffuse_light_img")
+    .image_array_out(1, Qualifier::READ_WRITE, GPU_RGBA16F, "rp_light_img")
     .image_out(2, Qualifier::READ_WRITE, GPU_RGBA16F, "rp_diffuse_color_img")
-    .image_out(3, Qualifier::READ_WRITE, GPU_RGBA16F, "rp_specular_light_img")
+    .image_out(3, Qualifier::READ_WRITE, GPU_RGBA16F, "rp_specular_color_img")
-    .image_out(4, Qualifier::READ_WRITE, GPU_RGBA16F, "rp_specular_color_img")
+    .image_out(4, Qualifier::READ_WRITE, GPU_RGBA16F, "rp_emission_img")
-    .image_out(5, Qualifier::READ_WRITE, GPU_RGBA16F, "rp_emission_img")
     .additional_info("eevee_aov_out",
                      "eevee_light_data",
                      "eevee_utility_texture",
@@ -138,11 +137,10 @@ GPU_SHADER_CREATE_INFO(eevee_surf_depth)
 GPU_SHADER_CREATE_INFO(eevee_surf_world)
     .vertex_out(eevee_surf_iface)
     .image_out(0, Qualifier::READ_WRITE, GPU_RGBA16F, "rp_normal_img")
-    .image_out(1, Qualifier::READ_WRITE, GPU_RGBA16F, "rp_diffuse_light_img")
+    .image_array_out(1, Qualifier::READ_WRITE, GPU_RGBA16F, "rp_light_img")
     .image_out(2, Qualifier::READ_WRITE, GPU_RGBA16F, "rp_diffuse_color_img")
-    .image_out(3, Qualifier::READ_WRITE, GPU_RGBA16F, "rp_specular_light_img")
+    .image_out(3, Qualifier::READ_WRITE, GPU_RGBA16F, "rp_specular_color_img")
-    .image_out(4, Qualifier::READ_WRITE, GPU_RGBA16F, "rp_specular_color_img")
+    .image_out(4, Qualifier::READ_WRITE, GPU_RGBA16F, "rp_emission_img")
-    .image_out(5, Qualifier::READ_WRITE, GPU_RGBA16F, "rp_emission_img")
     .push_constant(Type::FLOAT, "world_opacity_fade")
     .fragment_out(0, Type::VEC4, "out_background")
     .fragment_source("eevee_surf_world_frag.glsl")