rdc-cli Skill

Overview

rdc-cli is a Unix-friendly command-line interface for RenderDoc GPU captures. It provides a daemon-backed architecture using JSON-RPC over TCP, a virtual filesystem (VFS) path namespace for navigating capture internals, and composable commands designed for shell pipelines, scripting, and CI assertions.

Install: pip install rdc-cli (requires a local RenderDoc build with Python bindings). Check setup: rdc doctor.

Core Workflow

Follow this session lifecycle for any capture analysis task:

1. Open a capture: rdc open path/to/capture.rdc
2. Inspect metadata: rdc info, rdc stats, rdc events
3. Navigate the VFS: rdc ls /, rdc ls /textures, rdc cat /pipelines/0
4. Analyze specifics: rdc shaders, rdc pipeline, rdc resources, rdc bindings
5. Debug shaders: rdc debug pixel X Y, rdc debug vertex EID VTXID, rdc debug thread EID GX GY GZ
6. Export data: rdc texture EID -o out.png, rdc rt EID, rdc buffer EID -o buf.bin, rdc log
7. Close the session: rdc close

Session Management

• Default session name: default (or value of $RDC_SESSION).
• Override per-command: rdc --session myname open capture.rdc.
• Check active session: rdc status.
• Navigate to a specific event: rdc goto EID.

Output Formats

All list/table commands default to TSV (tab-separated values) with a header row, suitable for cut, awk, and sort.

Example -- get all draw call EIDs as a plain list:

rdc draws -q

Example -- JSON pipeline with jq:

rdc events --json | jq '.[] | select(.type == "DrawIndexed")'

Render Pass Analysis

List passes (Phase 8 columns)

rdc passes outputs 6 columns: NAME, DRAWS, DISPATCHES, TRIANGLES, BEGIN_EID, END_EID.

rdc passes                          # TSV table
rdc passes --json                   # includes load_ops/store_ops per pass
rdc passes --switches               # adds RT_SWITCHES column (TBR optimization)
rdc passes --deps --table           # per-pass READS/WRITES/LOAD/STORE

Inspect a single pass

rdc pass <name> shows enriched attachments: resource name, format, dimensions, and load/store ops.

rdc pass GBuffer
rdc pass GBuffer --json
rdc pass 0                          # by 0-based index

Detect dead render targets

rdc unused-targets finds render targets written but never consumed by visible output. Columns: ID, NAME, WRITTEN_BY, WAVE.

rdc unused-targets                  # TSV
rdc unused-targets --json           # structured
rdc unused-targets -q               # one resource ID per line (for scripting)

Frame statistics

rdc stats outputs three sections: Per-Pass Breakdown, Top Draws by Triangle Count, and Largest Resources.

rdc stats                           # all three sections
rdc stats --json                    # includes largest_resources array

GL/GLES/D3D11 captures without native BeginPass/EndPass markers get synthetic pass inference automatically — no extra flags needed.

Common Tasks

Find all draw calls

rdc draws
rdc draws --pass "GBuffer" --json

Trace a pixel

rdc debug pixel 512 384
rdc debug pixel 512 384 --json    # structured output
rdc debug pixel 512 384 --trace   # full step-by-step trace

Search shaders by name or source

rdc search "main" --type shader
rdc shaders --name "GBuffer*"

Export render targets

rdc rt EID -o output.png
rdc texture EID --format png -o tex.png

Browse VFS paths

rdc ls /
rdc ls /textures -l
rdc tree /pipelines --depth 2
rdc cat /events/42

Inspect pipeline state at a draw call

rdc goto EID
rdc pipeline --json
rdc bindings --json

Compare state before/after a pass

rdc goto 100 && rdc pipeline --json > before.json
rdc goto 200 && rdc pipeline --json > after.json
diff before.json after.json

CI Assertions

rdc-cli provides assertion commands that exit non-zero on failure, designed for automated testing pipelines:

Example CI script:

#!/bin/bash
set -e
rdc open test_capture.rdc
rdc assert-clean
rdc assert-count --type DrawIndexed --min 10
rdc assert-pixel 256 256 --expect 1.0,0.0,0.0,1.0
rdc close

Shader Edit-Replay

Modify and replay shaders without recompiling the application:

rdc shader-encodings EID          # list available encodings
rdc shader EID --source > s.frag  # extract shader source
# ... edit s.frag ...
rdc shader-build s.frag --encoding glsl  # compile edited shader
rdc shader-replace EID s.frag     # hot-swap into capture
rdc shader-restore EID            # revert single shader
rdc shader-restore-all            # revert all modifications

Command Reference

For the complete list of all commands with their arguments, options, types, and defaults, see references/commands-quick-ref.md.