-
-
Notifications
You must be signed in to change notification settings - Fork 3.6k
New issue
Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.
By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.
Already on GitHub? Sign in to your account
StandardMaterial
Light Transmission
#8015
Merged
Merged
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
coreh
changed the title
Mar 10, 2023
StandardMaterial
TransmissionStandardMaterial
Light Transmission
JMS55
added
C-Feature
A new feature, making something new possible
A-Rendering
Drawing game state to the screen
labels
Mar 10, 2023
A couple of notes:
|
…ace, then projecting to view
github-merge-queue bot
pushed a commit
that referenced
this pull request
Oct 31, 2023
# Objective Right now, we flip the `world_normal` in response to `double_sided && !is_front`, however when calculating `N` from tangents and the normal map, we don't flip the normal read from the normal map, which produces extremely weird results. ## Solution - Pass `double_sided` and `is_front` flags to the `apply_normal_mapping()` function and use them to conditionally flip `Nt` ## Comparison Note: These are from a custom scene running with the `transmission` branch, (#8015) I noticed lighting got pretty weird for the back side of translucent `double_sided` materials whenever I added a normal map. ### Before <img width="1392" alt="Screenshot 2023-10-31 at 01 26 06" src="https://github.com/bevyengine/bevy/assets/418473/d5f8c9c3-aca1-4c2f-854d-f0d0fd2fb19a"> ### After <img width="1392" alt="Screenshot 2023-10-31 at 01 25 42" src="https://github.com/bevyengine/bevy/assets/418473/fa0e1aa2-19ad-4c27-bb08-37299d97971c"> --- ## Changelog - Fixed a bug where `StandardMaterial::double_sided` would interact incorrectly with normal maps, producing broken results.
ameknite
pushed a commit
to ameknite/bevy
that referenced
this pull request
Nov 6, 2023
# Objective - This PR aims to make the various `*_PREPASS` shader defs we have (`NORMAL_PREPASS`, `DEPTH_PREPASS`, `MOTION_VECTORS_PREPASS` AND `DEFERRED_PREPASS`) easier to use and understand: - So that their meaning is now consistent across all contexts; (“prepass X is enabled for the current view”) - So that they're also consistently set across all contexts. - It also aims to enable us to (with a follow up PR) to conditionally gate the `BindGroupEntry` and `BindGroupLayoutEntry` items associated with these prepasses, saving us up to 4 texture slots in WebGL (currently globally limited to 16 per shader, regardless of bind groups) ## Solution - We now consistently set these from `PrepassPipeline`, the `MeshPipeline` and the `DeferredLightingPipeline`, we also set their `MeshPipelineKey`s; - We introduce `PREPASS_PIPELINE`, `MESH_PIPELINE` and `DEFERRED_LIGHTING_PIPELINE` that can be used to detect where the code is running, without overloading the meanings of the prepass shader defs; - We also gate the WGSL functions in `bevy_pbr::prepass_utils` with `#ifdef`s for their respective shader defs, so that shader code can provide a fallback whenever they're not available. - This allows us to conditionally include the bindings for these prepass textures (My next PR, which will hopefully unblock bevyengine#8015) - @robtfm mentioned [these were being used to prevent accessing the same binding as read/write in the prepass](https://discord.com/channels/691052431525675048/743663924229963868/1163270458393759814), however even after reversing the `#ifndef`s I had no issues running the code, so perhaps the compiler is already smart enough even without tree shaking to know they're not being used, thanks to `#ifdef PREPASS_PIPELINE`? ## Comparison ### Before | Shader Def | `PrepassPipeline` | `MeshPipeline` | `DeferredLightingPipeline` | | ------------------------ | ----------------- | -------------- | -------------------------- | | `NORMAL_PREPASS` | Yes | No | No | | `DEPTH_PREPASS` | Yes | No | No | | `MOTION_VECTORS_PREPASS` | Yes | No | No | | `DEFERRED_PREPASS` | Yes | No | No | | View Key | `PrepassPipeline` | `MeshPipeline` | `DeferredLightingPipeline` | | ------------------------ | ----------------- | -------------- | -------------------------- | | `NORMAL_PREPASS` | Yes | Yes | No | | `DEPTH_PREPASS` | Yes | No | No | | `MOTION_VECTORS_PREPASS` | Yes | No | No | | `DEFERRED_PREPASS` | Yes | Yes\* | No | \* Accidentally was being set twice, once with only `deferred_prepass.is_some()` as a condition, and once with `deferred_p repass.is_some() && !forward` as a condition. ### After | Shader Def | `PrepassPipeline` | `MeshPipeline` | `DeferredLightingPipeline` | | ---------------------------- | ----------------- | --------------- | -------------------------- | | `NORMAL_PREPASS` | Yes | Yes | Yes | | `DEPTH_PREPASS` | Yes | Yes | Yes | | `MOTION_VECTORS_PREPASS` | Yes | Yes | Yes | | `DEFERRED_PREPASS` | Yes | Yes | Unconditionally | | `PREPASS_PIPELINE` | Unconditionally | No | No | | `MESH_PIPELINE` | No | Unconditionally | No | | `DEFERRED_LIGHTING_PIPELINE` | No | No | Unconditionally | | View Key | `PrepassPipeline` | `MeshPipeline` | `DeferredLightingPipeline` | | ------------------------ | ----------------- | -------------- | -------------------------- | | `NORMAL_PREPASS` | Yes | Yes | Yes | | `DEPTH_PREPASS` | Yes | Yes | Yes | | `MOTION_VECTORS_PREPASS` | Yes | Yes | Yes | | `DEFERRED_PREPASS` | Yes | Yes | Unconditionally | --- ## Changelog - Cleaned up WGSL `*_PREPASS` shader defs so they're now consistently used everywhere; - Introduced `PREPASS_PIPELINE`, `MESH_PIPELINE` and `DEFERRED_LIGHTING_PIPELINE` WGSL shader defs for conditionally compiling logic based the current pipeline; - WGSL functions from `bevy_pbr::prepass_utils` are now guarded with `#ifdef` based on the currently enabled prepasses; ## Migration Guide - When using functions from `bevy_pbr::prepass_utils` (`prepass_depth()`, `prepass_normal()`, `prepass_motion_vector()`) in contexts where these prepasses might be disabled, you should now wrap your calls with the appropriate `#ifdef` guards, (`#ifdef DEPTH_PREPASS`, `#ifdef NORMAL_PREPASS`, `#ifdef MOTION_VECTOR_PREPASS`) providing fallback logic where applicable. --------- Co-authored-by: Carter Anderson <[email protected]> Co-authored-by: IceSentry <[email protected]>
ameknite
pushed a commit
to ameknite/bevy
that referenced
this pull request
Nov 6, 2023
# Objective This PR aims to make it so that we don't accidentally go over `MAX_TEXTURE_IMAGE_UNITS` (in WebGL) or `maxSampledTexturesPerShaderStage` (in WebGPU), giving us some extra leeway to add more view bind group textures. (This PR is extracted from—and unblocks—bevyengine#8015) ## Solution - We replace the existing `view_layout` and `view_layout_multisampled` pair with an array of 32 bind group layouts, generated ahead of time; - For now, these layouts cover all the possible combinations of: `multisampled`, `depth_prepass`, `normal_prepass`, `motion_vector_prepass` and `deferred_prepass`: - In the future, as @JMS55 pointed out, we can likely take out `motion_vector_prepass` and `deferred_prepass`, as these are not really needed for the mesh pipeline and can use separate pipelines. This would bring the possible combinations down to 8; - We can also add more "optional" textures as they become needed, allowing the engine to scale to a wider variety of use cases in lower end/web environments (e.g. some apps might just want normal and depth prepasses, others might only want light probes), while still keeping a high ceiling for high end native environments where more textures are supported. - While preallocating bind group layouts is relatively cheap, the number of combinations grows exponentially, so we should likely limit ourselves to something like at most 256–1024 total layouts until we find a better solution (like generating them lazily) - To make this mechanism a little bit more explicit/discoverable, so that compatibility with WebGPU/WebGL is not broken by accident, we add a `MESH_PIPELINE_VIEW_LAYOUT_SAFE_MAX_TEXTURES` const and warn whenever the number of textures in the layout crosses it. - The warning is gated by `#[cfg(debug_assertions)]` and not issued in release builds; - We're counting the actual textures in the bind group layout instead of using some roundabout metric so it should be accurate; - Right now `MESH_PIPELINE_VIEW_LAYOUT_SAFE_MAX_TEXTURES` is set to 10 in order to leave 6 textures free for other groups; - Currently there's no combination that would cause us to go over the limit, but that will change once bevyengine#8015 lands. --- ## Changelog - `MeshPipeline` view bind group layouts now vary based on the current multisampling and prepass states, saving a couple of texture binding entries when prepasses are not in use. ## Migration Guide - `MeshPipeline::view_layout` and `MeshPipeline::view_layout_multisampled` have been replaced with a private array to accomodate for variable view bind group layouts. To obtain a view bind group layout for the current pipeline state, use the new `MeshPipeline::get_view_layout()` or `MeshPipeline::get_view_layout_from_key()` methods.
ameknite
pushed a commit
to ameknite/bevy
that referenced
this pull request
Nov 6, 2023
# Objective Right now, we flip the `world_normal` in response to `double_sided && !is_front`, however when calculating `N` from tangents and the normal map, we don't flip the normal read from the normal map, which produces extremely weird results. ## Solution - Pass `double_sided` and `is_front` flags to the `apply_normal_mapping()` function and use them to conditionally flip `Nt` ## Comparison Note: These are from a custom scene running with the `transmission` branch, (bevyengine#8015) I noticed lighting got pretty weird for the back side of translucent `double_sided` materials whenever I added a normal map. ### Before <img width="1392" alt="Screenshot 2023-10-31 at 01 26 06" src="https://github.com/bevyengine/bevy/assets/418473/d5f8c9c3-aca1-4c2f-854d-f0d0fd2fb19a"> ### After <img width="1392" alt="Screenshot 2023-10-31 at 01 25 42" src="https://github.com/bevyengine/bevy/assets/418473/fa0e1aa2-19ad-4c27-bb08-37299d97971c"> --- ## Changelog - Fixed a bug where `StandardMaterial::double_sided` would interact incorrectly with normal maps, producing broken results.
ameknite
pushed a commit
to ameknite/bevy
that referenced
this pull request
Nov 6, 2023
# Objective <img width="1920" alt="Screenshot 2023-04-26 at 01 07 34" src="https://user-images.githubusercontent.com/418473/234467578-0f34187b-5863-4ea1-88e9-7a6bb8ce8da3.png"> This PR adds both diffuse and specular light transmission capabilities to the `StandardMaterial`, with support for screen space refractions. This enables realistically representing a wide range of real-world materials, such as: - Glass; (Including frosted glass) - Transparent and translucent plastics; - Various liquids and gels; - Gemstones; - Marble; - Wax; - Paper; - Leaves; - Porcelain. Unlike existing support for transparency, light transmission does not rely on fixed function alpha blending, and therefore works with both `AlphaMode::Opaque` and `AlphaMode::Mask` materials. ## Solution - Introduces a number of transmission related fields in the `StandardMaterial`; - For specular transmission: - Adds logic to take a view main texture snapshot after the opaque phase; (in order to perform screen space refractions) - Introduces a new `Transmissive3d` phase to the renderer, to which all meshes with `transmission > 0.0` materials are sent. - Calculates a light exit point (of the approximate mesh volume) using `ior` and `thickness` properties - Samples the snapshot texture with an adaptive number of taps across a `roughness`-controlled radius enabling “blurry” refractions - For diffuse transmission: - Approximates transmitted diffuse light by using a second, flipped + displaced, diffuse-only Lambertian lobe for each light source. ## To Do - [x] Figure out where `fresnel_mix()` is taking place, if at all, and where `dielectric_specular` is being calculated, if at all, and update them to use the `ior` value (Not a blocker, just a nice-to-have for more correct BSDF) - To the _best of my knowledge, this is now taking place, after 964340c. The fresnel mix is actually "split" into two parts in our implementation, one `(1 - fresnel(...))` in the transmission, and `fresnel()` in the light implementations. A surface with more reflectance now will produce slightly dimmer transmission towards the grazing angle, as more of the light gets reflected. - [x] Add `transmission_texture` - [x] Add `diffuse_transmission_texture` - [x] Add `thickness_texture` - [x] Add `attenuation_distance` and `attenuation_color` - [x] Connect values to glTF loader - [x] `transmission` and `transmission_texture` - [x] `thickness` and `thickness_texture` - [x] `ior` - [ ] `diffuse_transmission` and `diffuse_transmission_texture` (needs upstream support in `gltf` crate, not a blocker) - [x] Add support for multiple screen space refraction “steps” - [x] Conditionally create no transmission snapshot texture at all if `steps == 0` - [x] Conditionally enable/disable screen space refraction transmission snapshots - [x] Read from depth pre-pass to prevent refracting pixels in front of the light exit point - [x] Use `interleaved_gradient_noise()` function for sampling blur in a way that benefits from TAA - [x] Drill down a TAA `#define`, tweak some aspects of the effect conditionally based on it - [x] Remove const array that's crashing under HLSL (unless a new `naga` release with gfx-rs/naga#2496 comes out before we merge this) - [ ] Look into alternatives to the `switch` hack for dynamically indexing the const array (might not be needed, compilers seem to be decent at expanding it) - [ ] Add pipeline keys for gating transmission (do we really want/need this?) - [x] Tweak some material field/function names? ## A Note on Texture Packing _This was originally added as a comment to the `specular_transmission_texture`, `thickness_texture` and `diffuse_transmission_texture` documentation, I removed it since it was more confusing than helpful, and will likely be made redundant/will need to be updated once we have a better infrastructure for preprocessing assets_ Due to how channels are mapped, you can more efficiently use a single shared texture image for configuring the following: - R - `specular_transmission_texture` - G - `thickness_texture` - B - _unused_ - A - `diffuse_transmission_texture` The `KHR_materials_diffuse_transmission` glTF extension also defines a `diffuseTransmissionColorTexture`, that _we don't currently support_. One might choose to pack the intensity and color textures together, using RGB for the color and A for the intensity, in which case this packing advice doesn't really apply. --- ## Changelog - Added a new `Transmissive3d` render phase for rendering specular transmissive materials with screen space refractions - Added rendering support for transmitted environment map light on the `StandardMaterial` as a fallback for screen space refractions - Added `diffuse_transmission`, `specular_transmission`, `thickness`, `ior`, `attenuation_distance` and `attenuation_color` to the `StandardMaterial` - Added `diffuse_transmission_texture`, `specular_transmission_texture`, `thickness_texture` to the `StandardMaterial`, gated behind a new `pbr_transmission_textures` cargo feature (off by default, for maximum hardware compatibility) - Added `Camera3d::screen_space_specular_transmission_steps` for controlling the number of “layers of transparency” rendered for transmissive objects - Added a `TransmittedShadowReceiver` component for enabling shadows in (diffusely) transmitted light. (disabled by default, as it requires carefully setting up the `thickness` to avoid self-shadow artifacts) - Added support for the `KHR_materials_transmission`, `KHR_materials_ior` and `KHR_materials_volume` glTF extensions - Renamed items related to temporal jitter for greater consistency ## Migration Guide - `SsaoPipelineKey::temporal_noise` has been renamed to `SsaoPipelineKey::temporal_jitter` - The `TAA` shader def (controlled by the presence of the `TemporalAntiAliasSettings` component in the camera) has been replaced with the `TEMPORAL_JITTER` shader def (controlled by the presence of the `TemporalJitter` component in the camera) - `MeshPipelineKey::TAA` has been replaced by `MeshPipelineKey::TEMPORAL_JITTER` - The `TEMPORAL_NOISE` shader def has been consolidated with `TEMPORAL_JITTER`
Great work @coreh and everyone else involved ❤️🎉 |
rdrpenguin04
pushed a commit
to rdrpenguin04/bevy
that referenced
this pull request
Jan 9, 2024
# Objective - This PR aims to make the various `*_PREPASS` shader defs we have (`NORMAL_PREPASS`, `DEPTH_PREPASS`, `MOTION_VECTORS_PREPASS` AND `DEFERRED_PREPASS`) easier to use and understand: - So that their meaning is now consistent across all contexts; (“prepass X is enabled for the current view”) - So that they're also consistently set across all contexts. - It also aims to enable us to (with a follow up PR) to conditionally gate the `BindGroupEntry` and `BindGroupLayoutEntry` items associated with these prepasses, saving us up to 4 texture slots in WebGL (currently globally limited to 16 per shader, regardless of bind groups) ## Solution - We now consistently set these from `PrepassPipeline`, the `MeshPipeline` and the `DeferredLightingPipeline`, we also set their `MeshPipelineKey`s; - We introduce `PREPASS_PIPELINE`, `MESH_PIPELINE` and `DEFERRED_LIGHTING_PIPELINE` that can be used to detect where the code is running, without overloading the meanings of the prepass shader defs; - We also gate the WGSL functions in `bevy_pbr::prepass_utils` with `#ifdef`s for their respective shader defs, so that shader code can provide a fallback whenever they're not available. - This allows us to conditionally include the bindings for these prepass textures (My next PR, which will hopefully unblock bevyengine#8015) - @robtfm mentioned [these were being used to prevent accessing the same binding as read/write in the prepass](https://discord.com/channels/691052431525675048/743663924229963868/1163270458393759814), however even after reversing the `#ifndef`s I had no issues running the code, so perhaps the compiler is already smart enough even without tree shaking to know they're not being used, thanks to `#ifdef PREPASS_PIPELINE`? ## Comparison ### Before | Shader Def | `PrepassPipeline` | `MeshPipeline` | `DeferredLightingPipeline` | | ------------------------ | ----------------- | -------------- | -------------------------- | | `NORMAL_PREPASS` | Yes | No | No | | `DEPTH_PREPASS` | Yes | No | No | | `MOTION_VECTORS_PREPASS` | Yes | No | No | | `DEFERRED_PREPASS` | Yes | No | No | | View Key | `PrepassPipeline` | `MeshPipeline` | `DeferredLightingPipeline` | | ------------------------ | ----------------- | -------------- | -------------------------- | | `NORMAL_PREPASS` | Yes | Yes | No | | `DEPTH_PREPASS` | Yes | No | No | | `MOTION_VECTORS_PREPASS` | Yes | No | No | | `DEFERRED_PREPASS` | Yes | Yes\* | No | \* Accidentally was being set twice, once with only `deferred_prepass.is_some()` as a condition, and once with `deferred_p repass.is_some() && !forward` as a condition. ### After | Shader Def | `PrepassPipeline` | `MeshPipeline` | `DeferredLightingPipeline` | | ---------------------------- | ----------------- | --------------- | -------------------------- | | `NORMAL_PREPASS` | Yes | Yes | Yes | | `DEPTH_PREPASS` | Yes | Yes | Yes | | `MOTION_VECTORS_PREPASS` | Yes | Yes | Yes | | `DEFERRED_PREPASS` | Yes | Yes | Unconditionally | | `PREPASS_PIPELINE` | Unconditionally | No | No | | `MESH_PIPELINE` | No | Unconditionally | No | | `DEFERRED_LIGHTING_PIPELINE` | No | No | Unconditionally | | View Key | `PrepassPipeline` | `MeshPipeline` | `DeferredLightingPipeline` | | ------------------------ | ----------------- | -------------- | -------------------------- | | `NORMAL_PREPASS` | Yes | Yes | Yes | | `DEPTH_PREPASS` | Yes | Yes | Yes | | `MOTION_VECTORS_PREPASS` | Yes | Yes | Yes | | `DEFERRED_PREPASS` | Yes | Yes | Unconditionally | --- ## Changelog - Cleaned up WGSL `*_PREPASS` shader defs so they're now consistently used everywhere; - Introduced `PREPASS_PIPELINE`, `MESH_PIPELINE` and `DEFERRED_LIGHTING_PIPELINE` WGSL shader defs for conditionally compiling logic based the current pipeline; - WGSL functions from `bevy_pbr::prepass_utils` are now guarded with `#ifdef` based on the currently enabled prepasses; ## Migration Guide - When using functions from `bevy_pbr::prepass_utils` (`prepass_depth()`, `prepass_normal()`, `prepass_motion_vector()`) in contexts where these prepasses might be disabled, you should now wrap your calls with the appropriate `#ifdef` guards, (`#ifdef DEPTH_PREPASS`, `#ifdef NORMAL_PREPASS`, `#ifdef MOTION_VECTOR_PREPASS`) providing fallback logic where applicable. --------- Co-authored-by: Carter Anderson <[email protected]> Co-authored-by: IceSentry <[email protected]>
rdrpenguin04
pushed a commit
to rdrpenguin04/bevy
that referenced
this pull request
Jan 9, 2024
# Objective This PR aims to make it so that we don't accidentally go over `MAX_TEXTURE_IMAGE_UNITS` (in WebGL) or `maxSampledTexturesPerShaderStage` (in WebGPU), giving us some extra leeway to add more view bind group textures. (This PR is extracted from—and unblocks—bevyengine#8015) ## Solution - We replace the existing `view_layout` and `view_layout_multisampled` pair with an array of 32 bind group layouts, generated ahead of time; - For now, these layouts cover all the possible combinations of: `multisampled`, `depth_prepass`, `normal_prepass`, `motion_vector_prepass` and `deferred_prepass`: - In the future, as @JMS55 pointed out, we can likely take out `motion_vector_prepass` and `deferred_prepass`, as these are not really needed for the mesh pipeline and can use separate pipelines. This would bring the possible combinations down to 8; - We can also add more "optional" textures as they become needed, allowing the engine to scale to a wider variety of use cases in lower end/web environments (e.g. some apps might just want normal and depth prepasses, others might only want light probes), while still keeping a high ceiling for high end native environments where more textures are supported. - While preallocating bind group layouts is relatively cheap, the number of combinations grows exponentially, so we should likely limit ourselves to something like at most 256–1024 total layouts until we find a better solution (like generating them lazily) - To make this mechanism a little bit more explicit/discoverable, so that compatibility with WebGPU/WebGL is not broken by accident, we add a `MESH_PIPELINE_VIEW_LAYOUT_SAFE_MAX_TEXTURES` const and warn whenever the number of textures in the layout crosses it. - The warning is gated by `#[cfg(debug_assertions)]` and not issued in release builds; - We're counting the actual textures in the bind group layout instead of using some roundabout metric so it should be accurate; - Right now `MESH_PIPELINE_VIEW_LAYOUT_SAFE_MAX_TEXTURES` is set to 10 in order to leave 6 textures free for other groups; - Currently there's no combination that would cause us to go over the limit, but that will change once bevyengine#8015 lands. --- ## Changelog - `MeshPipeline` view bind group layouts now vary based on the current multisampling and prepass states, saving a couple of texture binding entries when prepasses are not in use. ## Migration Guide - `MeshPipeline::view_layout` and `MeshPipeline::view_layout_multisampled` have been replaced with a private array to accomodate for variable view bind group layouts. To obtain a view bind group layout for the current pipeline state, use the new `MeshPipeline::get_view_layout()` or `MeshPipeline::get_view_layout_from_key()` methods.
rdrpenguin04
pushed a commit
to rdrpenguin04/bevy
that referenced
this pull request
Jan 9, 2024
# Objective Right now, we flip the `world_normal` in response to `double_sided && !is_front`, however when calculating `N` from tangents and the normal map, we don't flip the normal read from the normal map, which produces extremely weird results. ## Solution - Pass `double_sided` and `is_front` flags to the `apply_normal_mapping()` function and use them to conditionally flip `Nt` ## Comparison Note: These are from a custom scene running with the `transmission` branch, (bevyengine#8015) I noticed lighting got pretty weird for the back side of translucent `double_sided` materials whenever I added a normal map. ### Before <img width="1392" alt="Screenshot 2023-10-31 at 01 26 06" src="https://github.com/bevyengine/bevy/assets/418473/d5f8c9c3-aca1-4c2f-854d-f0d0fd2fb19a"> ### After <img width="1392" alt="Screenshot 2023-10-31 at 01 25 42" src="https://github.com/bevyengine/bevy/assets/418473/fa0e1aa2-19ad-4c27-bb08-37299d97971c"> --- ## Changelog - Fixed a bug where `StandardMaterial::double_sided` would interact incorrectly with normal maps, producing broken results.
rdrpenguin04
pushed a commit
to rdrpenguin04/bevy
that referenced
this pull request
Jan 9, 2024
# Objective <img width="1920" alt="Screenshot 2023-04-26 at 01 07 34" src="https://user-images.githubusercontent.com/418473/234467578-0f34187b-5863-4ea1-88e9-7a6bb8ce8da3.png"> This PR adds both diffuse and specular light transmission capabilities to the `StandardMaterial`, with support for screen space refractions. This enables realistically representing a wide range of real-world materials, such as: - Glass; (Including frosted glass) - Transparent and translucent plastics; - Various liquids and gels; - Gemstones; - Marble; - Wax; - Paper; - Leaves; - Porcelain. Unlike existing support for transparency, light transmission does not rely on fixed function alpha blending, and therefore works with both `AlphaMode::Opaque` and `AlphaMode::Mask` materials. ## Solution - Introduces a number of transmission related fields in the `StandardMaterial`; - For specular transmission: - Adds logic to take a view main texture snapshot after the opaque phase; (in order to perform screen space refractions) - Introduces a new `Transmissive3d` phase to the renderer, to which all meshes with `transmission > 0.0` materials are sent. - Calculates a light exit point (of the approximate mesh volume) using `ior` and `thickness` properties - Samples the snapshot texture with an adaptive number of taps across a `roughness`-controlled radius enabling “blurry” refractions - For diffuse transmission: - Approximates transmitted diffuse light by using a second, flipped + displaced, diffuse-only Lambertian lobe for each light source. ## To Do - [x] Figure out where `fresnel_mix()` is taking place, if at all, and where `dielectric_specular` is being calculated, if at all, and update them to use the `ior` value (Not a blocker, just a nice-to-have for more correct BSDF) - To the _best of my knowledge, this is now taking place, after 964340c. The fresnel mix is actually "split" into two parts in our implementation, one `(1 - fresnel(...))` in the transmission, and `fresnel()` in the light implementations. A surface with more reflectance now will produce slightly dimmer transmission towards the grazing angle, as more of the light gets reflected. - [x] Add `transmission_texture` - [x] Add `diffuse_transmission_texture` - [x] Add `thickness_texture` - [x] Add `attenuation_distance` and `attenuation_color` - [x] Connect values to glTF loader - [x] `transmission` and `transmission_texture` - [x] `thickness` and `thickness_texture` - [x] `ior` - [ ] `diffuse_transmission` and `diffuse_transmission_texture` (needs upstream support in `gltf` crate, not a blocker) - [x] Add support for multiple screen space refraction “steps” - [x] Conditionally create no transmission snapshot texture at all if `steps == 0` - [x] Conditionally enable/disable screen space refraction transmission snapshots - [x] Read from depth pre-pass to prevent refracting pixels in front of the light exit point - [x] Use `interleaved_gradient_noise()` function for sampling blur in a way that benefits from TAA - [x] Drill down a TAA `#define`, tweak some aspects of the effect conditionally based on it - [x] Remove const array that's crashing under HLSL (unless a new `naga` release with gfx-rs/naga#2496 comes out before we merge this) - [ ] Look into alternatives to the `switch` hack for dynamically indexing the const array (might not be needed, compilers seem to be decent at expanding it) - [ ] Add pipeline keys for gating transmission (do we really want/need this?) - [x] Tweak some material field/function names? ## A Note on Texture Packing _This was originally added as a comment to the `specular_transmission_texture`, `thickness_texture` and `diffuse_transmission_texture` documentation, I removed it since it was more confusing than helpful, and will likely be made redundant/will need to be updated once we have a better infrastructure for preprocessing assets_ Due to how channels are mapped, you can more efficiently use a single shared texture image for configuring the following: - R - `specular_transmission_texture` - G - `thickness_texture` - B - _unused_ - A - `diffuse_transmission_texture` The `KHR_materials_diffuse_transmission` glTF extension also defines a `diffuseTransmissionColorTexture`, that _we don't currently support_. One might choose to pack the intensity and color textures together, using RGB for the color and A for the intensity, in which case this packing advice doesn't really apply. --- ## Changelog - Added a new `Transmissive3d` render phase for rendering specular transmissive materials with screen space refractions - Added rendering support for transmitted environment map light on the `StandardMaterial` as a fallback for screen space refractions - Added `diffuse_transmission`, `specular_transmission`, `thickness`, `ior`, `attenuation_distance` and `attenuation_color` to the `StandardMaterial` - Added `diffuse_transmission_texture`, `specular_transmission_texture`, `thickness_texture` to the `StandardMaterial`, gated behind a new `pbr_transmission_textures` cargo feature (off by default, for maximum hardware compatibility) - Added `Camera3d::screen_space_specular_transmission_steps` for controlling the number of “layers of transparency” rendered for transmissive objects - Added a `TransmittedShadowReceiver` component for enabling shadows in (diffusely) transmitted light. (disabled by default, as it requires carefully setting up the `thickness` to avoid self-shadow artifacts) - Added support for the `KHR_materials_transmission`, `KHR_materials_ior` and `KHR_materials_volume` glTF extensions - Renamed items related to temporal jitter for greater consistency ## Migration Guide - `SsaoPipelineKey::temporal_noise` has been renamed to `SsaoPipelineKey::temporal_jitter` - The `TAA` shader def (controlled by the presence of the `TemporalAntiAliasSettings` component in the camera) has been replaced with the `TEMPORAL_JITTER` shader def (controlled by the presence of the `TemporalJitter` component in the camera) - `MeshPipelineKey::TAA` has been replaced by `MeshPipelineKey::TEMPORAL_JITTER` - The `TEMPORAL_NOISE` shader def has been consolidated with `TEMPORAL_JITTER`
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Labels
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Objective
This PR adds both diffuse and specular light transmission capabilities to the
StandardMaterial
, with support for screen space refractions. This enables realistically representing a wide range of real-world materials, such as:Unlike existing support for transparency, light transmission does not rely on fixed function alpha blending, and therefore works with both
AlphaMode::Opaque
andAlphaMode::Mask
materials.Solution
StandardMaterial
;Transmissive3d
phase to the renderer, to which all meshes withtransmission > 0.0
materials are sent.ior
andthickness
propertiesroughness
-controlled radius enabling “blurry” refractionsTo Do
fresnel_mix()
is taking place, if at all, and wheredielectric_specular
is being calculated, if at all, and update them to use theior
value (Not a blocker, just a nice-to-have for more correct BSDF)(1 - fresnel(...))
in the transmission, andfresnel()
in the light implementations. A surface with more reflectance now will produce slightly dimmer transmission towards the grazing angle, as more of the light gets reflected.transmission_texture
diffuse_transmission_texture
thickness_texture
attenuation_distance
andattenuation_color
transmission
andtransmission_texture
thickness
andthickness_texture
ior
diffuse_transmission
anddiffuse_transmission_texture
(needs upstream support ingltf
crate, not a blocker)steps == 0
interleaved_gradient_noise()
function for sampling blur in a way that benefits from TAA#define
, tweak some aspects of the effect conditionally based on itnaga
release with [wgsl-in] Use deterministic ordering for dependency ordering. gfx-rs/naga#2496 comes out before we merge this)switch
hack for dynamically indexing the const array (might not be needed, compilers seem to be decent at expanding it)A Note on Texture Packing
This was originally added as a comment to the
specular_transmission_texture
,thickness_texture
anddiffuse_transmission_texture
documentation, I removed it since it was more confusing than helpful, and will likely be made redundant/will need to be updated once we have a better infrastructure for preprocessing assetsDue to how channels are mapped, you can more efficiently use a single shared texture image
for configuring the following:
specular_transmission_texture
thickness_texture
diffuse_transmission_texture
The
KHR_materials_diffuse_transmission
glTF extension also defines adiffuseTransmissionColorTexture
,that we don't currently support. One might choose to pack the intensity and color textures together,
using RGB for the color and A for the intensity, in which case this packing advice doesn't really apply.
Changelog
Transmissive3d
render phase for rendering specular transmissive materials with screen space refractionsStandardMaterial
as a fallback for screen space refractionsdiffuse_transmission
,specular_transmission
,thickness
,ior
,attenuation_distance
andattenuation_color
to theStandardMaterial
diffuse_transmission_texture
,specular_transmission_texture
,thickness_texture
to theStandardMaterial
, gated behind a newpbr_transmission_textures
cargo feature (off by default, for maximum hardware compatibility)Camera3d::screen_space_specular_transmission_steps
for controlling the number of “layers of transparency” rendered for transmissive objectsTransmittedShadowReceiver
component for enabling shadows in (diffusely) transmitted light. (disabled by default, as it requires carefully setting up thethickness
to avoid self-shadow artifacts)KHR_materials_transmission
,KHR_materials_ior
andKHR_materials_volume
glTF extensionsMigration Guide
SsaoPipelineKey::temporal_noise
has been renamed toSsaoPipelineKey::temporal_jitter
TAA
shader def (controlled by the presence of theTemporalAntiAliasSettings
component in the camera) has been replaced with theTEMPORAL_JITTER
shader def (controlled by the presence of theTemporalJitter
component in the camera)MeshPipelineKey::TAA
has been replaced byMeshPipelineKey::TEMPORAL_JITTER
TEMPORAL_NOISE
shader def has been consolidated withTEMPORAL_JITTER