NEWS
sd2R 0.2.1
- FLUX.2 (Klein 4B) support via
model_type = "flux2", with auto-detection from tensors/filename.
- New
llm_path argument in sd_ctx() for LLM text encoders (Qwen3 for FLUX.2 Klein, Mistral-Small for full FLUX.2).
sd2R 0.2.0
Performance: VAE Decode ×24 Faster
vae_conv_direct now defaults to TRUE — VAE decoder uses GGML_OP_CONV_2D
(direct convolution via conv2d_mm.comp) instead of the legacy IM2COL + MUL_MAT path.- On RX 9070 (RDNA4) with Vulkan coopmat (KHR): VAE decode 12.6s → 0.5s for 768×768.
- All convolutions now run through the coopmat cm1 path (~16-17 TFLOPS/s) when
coopmat_support is available; scalar FMA fallback used otherwise.
sd2R 0.1.9 (2026-04-09)
Shiny GUI
- New
sd_app() launches an interactive Shiny application for image generation.
- Auto-detection of model architecture (Flux, SD3, SDXL, SD1/2) from filenames
in the models folder — no manual configuration needed.
- Non-blocking async generation via C++
std::thread: the UI remains responsive
during image generation, with a live progress bar and ETA display.
- Automatic role assignment for multi-file models (diffusion, VAE, CLIP-L, T5-XXL).
- Prevents loading incompatible model combinations (e.g. SD1.5 + Flux).
Async C++ Generation API
- New internal functions for non-blocking generation from R:
sd_generate_async() — launches generation in a background C++ thread.sd_generate_poll() — checks completion status (atomic flags).sd_generate_result() — retrieves results after completion.
- Progress callback writes JSON to a temp file (
step, steps, pct,
elapsed, eta_sec), read by Shiny via later::later() polling.
- R API calls (
Rprintf, R_CheckUserInterrupt) are suppressed in the
worker thread to prevent stack corruption.
Build System
tools/patch_sd_sources.sh rewritten: all sed calls replaced with
perl -pi -e for cross-platform compatibility (macOS BSD sed + Linux GNU sed).
sd2R 0.1.8
Bug Fixes
- Fixed
undefined symbol: ggml_backend_vk_get_device_count load error on
CRAN Fedora (clang and gcc). Root cause: ggmlR's shared library (ggmlR.so)
was built with Vulkan, but the static library (libggml.a) shipped without
Vulkan objects. The old configure relied on ggml_vulkan_status() which
queries ggmlR.so — it reported "AVAILABLE", causing sd2R to compile with
-DSD_USE_VULKAN against a libggml.a that lacked the symbols.
Now configure checks nm libggml.a for a defined (T) symbol directly,
ignoring the runtime ggmlR check entirely.
sd2R 0.1.7 (2026-03-30)
Multi-GPU Model Parallelism
- New
device_layout parameter in sd_ctx(): distribute sub-models across
multiple Vulkan GPUs without separate processes.
"mono" — all on one GPU (default, backward-compatible)."split_encoders" — CLIP/T5 on GPU 1, diffusion + VAE on GPU 0."split_vae" — CLIP/T5 + VAE on GPU 1, diffusion on GPU 0."encoders_cpu" — text encoders on CPU, diffusion + VAE on GPU.
- Low-level
diffusion_gpu, clip_gpu, vae_gpu integer arguments for
manual device assignment (override presets).
Profiling
- New profiling API for per-stage timing of image generation:
sd_profile_start() / sd_profile_stop() — control event capture.sd_profile_get() — raw event data frame.sd_profile_summary() — formatted summary with durations and percentages.
- Stages tracked:
text_encode (with text_encode_clip and text_encode_t5
sub-stages), sampling, vae_decode, vae_encode, model loading.
- Pretty-printed output via
print.sd_profile().
sd2R 0.1.6
Pipeline Graph API
- New
sd_pipeline() / sd_node() — sequential graph-based pipeline.
Node types: "txt2img", "img2img", "upscale", "save".
sd_run_pipeline(pipeline, ctx) — execute pipeline with a single context.sd_save_pipeline() / sd_load_pipeline() — JSON serialization.
sd2R 0.1.5
Flux Support
- Flux model family (flux1-dev, etc.) fully supported: text-to-image,
image-to-image, highres fix, tiled sampling, multi-GPU.
- Separate model paths:
diffusion_model_path, vae_path, clip_l_path,
t5xxl_path in sd_ctx().
cfg_scale auto-defaults to 1.0 for Flux (guidance-distilled models).
img2img Improvements
sd_generate() now defaults width/height to init image dimensions
when not specified explicitly.
sd2R 0.1.4
Build System
configure.win rewritten to use template approach (Makevars.win.in →
Makevars.win), matching ggmlR pattern.
sd2R 0.1.3
Unified sd_generate() Entry Point
- New
sd_generate() — single function for all generation modes. Automatically
selects the optimal strategy (direct, tiled sampling, or highres fix) based
on output resolution and available VRAM.
vram_gb parameter in sd_ctx(): set once, auto-routing handles the rest.
Multi-GPU
- New
sd_generate_multi_gpu() — parallel generation across multiple Vulkan
GPUs via callr, one process per GPU, with progress reporting.
Performance
- Batch compute optimization for tiled sampling: pre-allocated compute context
buffer eliminates ~110 MB malloc/free per UNet call.
sd2R 0.1.2
Highres Fix
- New
sd_highres_fix() — classic two-pass highres pipeline:
txt2img at native resolution → upscale → tiled img2img refinement.
hr_strength parameter (default 0.4) controls refinement intensity.
Tiled img2img
- New
sd_img2img_tiled() — img2img with MultiDiffusion tiled sampling for
large images.
sd2R 0.1.1
VAE Tiling
- New
vae_mode parameter: "normal", "tiled", "auto" (default).
Auto-tiles when image area exceeds threshold.
vae_tile_rel_x / vae_tile_rel_y for adaptive tile sizing.
High-Resolution Pipeline
- New
sd_txt2img_highres() — patch-based generation for 2K, 4K+ images.
model_type parameter in sd_ctx(): "sd1", "sd2", "sdxl", "flux",
"sd3".
Tiled Sampling (MultiDiffusion)
- New
sd_txt2img_tiled() — tiled diffusion sampling at any resolution.
VRAM bounded by tile size, not output resolution.
sd2R 0.1.0
Core
- Text-to-image generation via stable-diffusion.cpp (C++ backend).
- Support for SD 1.x, SD 2.x, SDXL model versions.
- SafeTensors and GGUF model format loading.
- Vulkan GPU backend via ggmlR.
- Samplers: Euler, Euler A, Heun, DPM2, DPM++ (2M), LCM, DDIM, TCD.
- Schedulers: Discrete, Karras, Exponential, Simple, SGM Uniform, AYS, LCM.
R API
sd_ctx() — create model context.sd_generate() — unified entry point.sd_txt2img(), sd_img2img() — low-level generation.sd_save_image(), sd_system_info().