orklev2-compositor

name	orklev2-compositor
description	Answer questions about orkid's compositor system, CompositingData/Scene/Technique, render nodes (Forward/Unlit/Picking), post-FX nodes (ACES/HSVG/Bloom/User), output nodes (Screen/RtGroup/VR/File), presets (ForwardPBR/Unlit/Picking), RtGroup render targets, and Python compositor bindings. Use when the user asks about compositing, post-processing, render targets, or rendering presets.
user-invocable	false

Orkid Compositor System Reference

When answering questions about compositing, post-processing, or render presets in orkid, consult the files below. All under ork.lev2/.

Key Files

Component	File
Core Compositor Structures	inc/ork/lev2/gfx/renderer/compositor.h
Node Base Classes	inc/ork/lev2/gfx/renderer/NodeCompositor/NodeCompositor.h
Compositor Material	inc/ork/lev2/gfx/renderer/compositormaterial.h
PBR Common (IBL/SSAO)	inc/ork/lev2/gfx/renderer/NodeCompositor/pbr_common.h
Render Targets	inc/ork/lev2/gfx/rtgroup.h
Forward Node	inc/ork/lev2/gfx/renderer/NodeCompositor/pbr_node_forward.h
Unlit Node	inc/ork/lev2/gfx/renderer/NodeCompositor/unlit_node.h
Screen Output	inc/ork/lev2/gfx/renderer/NodeCompositor/NodeCompositorScreen.h
RtGroup Output	inc/ork/lev2/gfx/renderer/NodeCompositor/OutputNodeRtGroup.h
VR Output	inc/ork/lev2/gfx/renderer/NodeCompositor/NodeCompositorVr.h
File Output	inc/ork/lev2/gfx/renderer/NodeCompositor/NodeCompositorFile.h
Post-FX ACES	inc/ork/lev2/gfx/renderer/NodeCompositor/PostFxNodeACES.h
Post-FX HSVG	inc/ork/lev2/gfx/renderer/NodeCompositor/PostFxNodeHSVG.h
Post-FX Bloom	inc/ork/lev2/gfx/renderer/NodeCompositor/PostFxNodeDecompBlur.h
Post-FX User	inc/ork/lev2/gfx/renderer/NodeCompositor/PostFxNodeUser.h
Preset Implementations	src/gfx/renderer/compositordata.cpp
CompositingImpl Runtime	src/gfx/renderer/compositorimpl.cpp
Node Implementations	src/gfx/renderer/NodeCompositor/
Forward Node Impl	src/gfx/renderer/NodeCompositor/forward/fwdnode_impl.h
Python Bindings	pyext/src/pyext_gfx_compositor.cpp

Architecture Overview

3-stage pipeline:

RenderCompositingNode ──→ PostCompositingNode(s) ──→ OutputCompositingNode
  (generate frame)         (effects chain)             (output sink)

Data Flow

CompositingData
  └─ CompositingScene
       └─ CompositingSceneItem
            └─ NodeCompositingTechnique
                 ├─ _renderNode (RenderCompositingNode)
                 ├─ _postEffectNodes (vector<PostCompositingNode>)
                 └─ _outputNode (OutputCompositingNode)

Runtime

CompositingImpl::assemble()
  └─ NodeCompositingTechnique::assemble()
       └─ _assemblerFn():
            1. outputNode->beginAssemble()
            2. renderNode->Render()
            3. outputNode->endAssemble()
            4. for each postFxNode: Render()
            5. Store final output

CompositingImpl::composite()
  └─ outputNode->composite()

Render Nodes

RenderCompositingNode (NodeCompositor.h:57) — Abstract Base

• _renderingmodel — e.g., "FORWARD_PBR"_crcu
• _layers — which scene layers to render
• DoRender(CompositorDrawData&) — pure virtual

ForwardNode (pbr_node_forward.h:17)

Full forward PBR rendering:

• Depth prepass → skybox → SSAO → color pass
• Environment probe updates
• Shadow map updates
• _pbrcommon — shared PBR resources (IBL, SSAO params)

UnlitNode (unlit_node.h:15)

Simple unlit rendering with configurable clear color.

PickingCompositingNode

Color-based object selection rendering.

Post-FX Nodes

PostCompositingNode (NodeCompositor.h:89) — Abstract Base

• _disabled — skip without removing from chain
• DoRender(CompositorDrawData&) — pure virtual
• GetOutputGroup() → rtgroup_ptr_t

PostFxNodeACES — ACES Tonemapping

• _exposure (float, default 1.0)
• Uses "framefx_aces" technique

PostFxNodeHSVG — Color Grading

• _hue (0.0), _saturation (1.0), _value (1.0), _gamma (1.0)

PostFxNodeDecompBlur — Bloom

• _threshold (0.5) — brightness cutoff
• _amount (0.5) — bloom intensity
• _blurfactor (1/32) — blur kernel scale
• _blurwidth (16) — blur kernel width

PostFxNodeUser — Custom Shader

• _shader_path — path to shader file
• _technique_name — technique to use
• _bindings — parameter map
• _double_buffer — ping-pong texture
• _flip_vertical — vertical flip

Op2CompositingNode — Binary Operations

• Two inputs (A, B) with scale/bias
• Modes: A*B, A/B, B/(A+C), A+B+C, lerp(A,B,C), solo

Output Nodes

OutputCompositingNode (NodeCompositor.h:27) — Abstract Base

• _flipY — flip Y axis (default true)
• beginAssemble() / endAssemble() / composite()
• Python callbacks: _onBeginAssemble, _onEndAssemble, _onCameraChange

ScreenOutputCompositingNode (NodeCompositorScreen.h:19)

• Direct screen/window output
• _supersample — supersampling factor
• _format — buffer format (RGBA8, RGBA32F, etc.)

RtGroupOutputCompositingNode (OutputNodeRtGroup.h:15)

• Render-to-texture output
• resize(w, h) — resize output
• _temporalFrames — temporal accumulation

VrOutputNode (NodeCompositorVr.h:29)

• Stereo VR output
• _distortion_lambda — barrel distortion callback
• Mono viewer mode option

DualMonoVrOutputNode (NodeCompositorVr.h:60)

• Dual-mono VR with external viewer window
• createExternalViewer() — secondary monitor window

FileOutputCompositingNode (NodeCompositorFile.h:50)

• Image sequence output
• Frame rates: 15/24/30/48/60/72/96/120/240 fps
• Resolutions: 640x480 through 1920x1080, with multipliers (Quarter–Quadruple)

Render Targets (rtgroup.h)

RtGroup (line 60) — Multiple Render Targets

• Max 8 MRT buffers (kmaxmrts)
• createRenderTarget(format, usage, with_texture) → rtbuffer_ptr_t
• createDepthBuffer(format, with_texture) → rtbuffer_ptr_t
• MSAA support, auto-clear, cube map mode

RtBuffer (line 27) — Single Buffer

• Format, dimensions, texture access
• Mip generation: NONE, AUTOCOMPUTE, USER
• Clear color/depth configuration

RtgSet (line 111) — Indexed Collection

• fetch(key) → get or create RtGroup by CRC key
• Used by render nodes for different output configurations

Presets (compositordata.cpp)

Preset	Method	Description
ForwardPBR	presetForwardPBR()	Forward PBR with optional skybox
Unlit	presetUnlit()	Simple unlit rendering
Picking	presetPicking()	Object selection pass
PickingDebug	presetPickingDebug()	Picking with screen output
ForwardPBRVR	presetForwardPBRVR()	Forward PBR for VR
ForwardPBRVRDM	presetForwardPBRVRDM()	Dual-mono VR

Note: DeferredPBR is currently disabled (OrkAssert(false)).

Each preset returns RenderPresetContext:

• _nodetek — technique
• _outputnode — output node
• _rendernode — render node

CompositorDrawData Properties

Key CRC-hashed properties passed through the pipeline:

Key	Type	Description
"render_out"	RtBuffer*	Render node output buffer
"render_outgroup"	rtgroup_ptr_t	Render node output group
"postfx_in"	rtgroup_ptr_t	Input to current post-FX
"final_out"	RtBuffer*	Final output buffer
"final_outgroup"	rtgroup_ptr_t	Final output group
"DB"	DrawQueue*	Drawable buffer

Python API

from orkengine import lev2

# Build compositor manually
comp_tek = lev2.NodeCompositingTechnique()
render_node = comp_tek.createRenderNode(lev2.ForwardNode, pbr_common)
output_node = comp_tek.createOutputNode(lev2.ScreenOutputCompositingNode)

# Add post-FX
aces = lev2.PostFxNodeACES()
aces.exposure = 1.5
comp_tek.postEffectNodes.append(aces)

bloom = lev2.PostFxNodeDecompBlur()
bloom.threshold = 0.8
bloom.amount = 0.3

hsvg = lev2.PostFxNodeHSVG()
hsvg.gamma = 2.2

# Scene setup
comp_data = lev2.CompositingData()
comp_scene = comp_data.createScene("scene1")
comp_item = comp_scene.createSceneItem("item1")
comp_item.technique = comp_tek

# Or use presets (via Scene constructor)
params = core.VarMap()
params.preset = "ForwardPBR"
params.SkyboxTexPathStr = "nebula"
scene = lev2.scenegraph.Scene(params)

# Output node callbacks
output_node.onBeginAssemble(lambda drawdata: ...)
output_node.onEndAssemble(lambda drawdata: ...)

# View data access
viewdata = drawdata.viewData
print(viewdata.camposmono)  # Camera position
print(viewdata.near, viewdata.far)

# Render node properties
render_node.layers = "std_forward"
render_node.debugRenderingModel = "FORWARD_PBR"

How to Answer

1. For compositor structure: check compositor.h data classes
2. For node types: check individual headers in NodeCompositor/
3. For presets: check compositordata.cpp (preset methods)
4. For forward rendering pipeline: check fwdnode_impl.h and fwdnode_impl_top.cpp
5. For post-FX: check individual PostFxNode*.h and .cpp files
6. For render targets: check rtgroup.h (RtGroup, RtBuffer, RtgSet)
7. For Python: check pyext_gfx_compositor.cpp
8. For PBR environment/SSAO: check pbr_common.h