blender-render

blender-render

Use render_scene for short stills. Use start_render_job for animation or multi-layer EXR or display-ready PNG / JPEG / TIFF / BMP output so the interactive Blender process remains responsive; poll with get_render_job and cancel only through the returned job id.

start_render_job accepts the output containers OPEN_EXR_MULTILAYER, OPEN_EXR, PNG, JPEG, TIFF, BMP. Omit output_format to reuse the scene's render.image_settings.file_format. A scene set to any other container is rejected before any frame renders rather than silently falling back to EXR — call set_render_settings or set_render_output to change it and resubmit.

Animation PNG resume/progress checks validate chunk CRCs, a complete zlib stream, and the filtered scanline layout (including Adam7), without calling bpy from status-query threads. They do not reconstruct pixels, validate all ancillary metadata, or establish visual quality. PNG files or inflated image data above 1 GiB, more than 1,000,000 total scanlines across all Adam7 passes, APNG, and unknown critical chunks fail closed. Each poll rechecks each job frame once, with bounded memory but work proportional to compressed and inflated image bytes; avoid tight polling of long/high-resolution sequences. A tracked PNG frame that becomes invalid after completion makes the job failed on its next query. Frames skipped at submission are not subsequently tracked by that job.

Other animation formats still use signature-only checks, which do not prove completeness. Independently decode EXR/JPEG/TIFF/BMP deliverables before trusting them; integrity support for those formats remains open in issue #315.

Use start_multiview_render_job for a bounded camera list (up to 8) and beauty/wire PNG deliverables. It saves an isolated copy of the current scene without changing the live filename, selection, materials, or settings. The worker uses factory startup with automatic scripts disabled. External assets must remain accessible; add-on-generated render dependencies are not loaded. Beauty uses the saved render engine (Cycles uses CPU) but bypasses compositor and sequencer to contain file output. Resolution is explicit and border rendering is disabled. Cameras render the current saved frame; camera animation markers are not used to select views.

Wire shows original mesh edges as physical tubes over the same unmodified mesh surfaces. Modifiers and shape keys are disabled, non-mesh geometry is omitted, and hidden render objects remain hidden. This is source topology, not evaluated modifier topology or a screen-space overlay. Radius is in local object units and scales with the object. The wire pass uses Cycles CPU. Requests exceeding the explicit max_source_edges budget (default 100,000; maximum 500,000) are rejected. Each PNG is decoded by Blender, dimension checked, and hashed; status reads verify the entire file hash. Failed images retain individual errors and do not make the batch successful.