Struct Diagnostics 

pub struct Diagnostics {

    pub a11y_sync: Diagnostic,
    pub ablate: Diagnostic,
    pub adpf: Diagnostic,
    pub assert_state_chain: Diagnostic,
    pub async_haptics: Diagnostic,
    pub background_pipelines: Diagnostic,
    pub compose_debug_modifiers: Diagnostic,
    pub compose_debug_slot_table: Diagnostic,
    pub core_pin: Diagnostic,
    pub debug_scope_labels: Diagnostic,
    pub desktop_frame_telemetry: Diagnostic,
    pub desktop_frame_telemetry_ms: Diagnostic,
    pub disable_nav_snap: Diagnostic,
    pub disable_scroll_translate: Diagnostic,
    pub disable_structural_dirt: Diagnostic,
    pub encode_delay_ms: Diagnostic,
    pub frame_lead_tenths: Diagnostic,
    pub frame_stage_telemetry: Diagnostic,
    pub frame_stage_telemetry_ms: Diagnostic,
    pub glass_material_folds: Diagnostic,
    pub gpu_fence_profile: Diagnostic,
    pub gpu_pass_timing: Diagnostic,
    pub gpu_shadow_cache_diag: Diagnostic,
    pub gpu_stage_diag: Diagnostic,
    pub gpu_stats: Diagnostic,
    pub layout_invalidation_dispatch_diag: Diagnostic,
    pub layout_measure_telemetry: Diagnostic,
    pub layout_measure_telemetry_ms: Diagnostic,
    pub layout_repass_schedule_diag: Diagnostic,
    pub lazy_cache_telemetry: Diagnostic,
    pub lazy_item_telemetry: Diagnostic,
    pub lazy_measure_telemetry: Diagnostic,
    pub location_key_diagnostics: Diagnostic,
    pub native_trace: Diagnostic,
    pub native_window_timing: Diagnostic,
    pub no_backdrop_cache: Diagnostic,
    pub no_effect_domains: Diagnostic,
    pub no_fill_cache: Diagnostic,
    pub no_interiors_first: Diagnostic,
    pub no_shader_flatten: Diagnostic,
    pub no_shader_fold: Diagnostic,
    pub no_shader_specialization: Diagnostic,
    pub pacing_diag: Diagnostic,
    pub pipeline_disk_cache: Diagnostic,
    pub present_thread: Diagnostic,
    pub probe_draw_passes: Diagnostic,
    pub probe_passes: Diagnostic,
    pub recompose_scope_telemetry_ms: Diagnostic,
    pub recomp_diag: Diagnostic,
    pub render_phase_dirty_diag: Diagnostic,
    pub robot_button_helper_diag: Diagnostic,
    pub scene_update_diag: Diagnostic,
    pub shape_variants: Diagnostic,
    pub skip_shadows: Diagnostic,
    pub structural_diag: Diagnostic,
    pub subcompose_telemetry: Diagnostic,
    pub survive_gpu_errors: Diagnostic,
    pub text_atlas_fallback_diag: Diagnostic,
    pub text_layout_telemetry: Diagnostic,
    pub update_stage_telemetry_ms: Diagnostic,
    pub validate_slots: Diagnostic,
    pub wgpu_render_stage_telemetry: Diagnostic,
    pub wgpu_render_stage_telemetry_ms: Diagnostic,
}

Every diagnostic and ablation switch, by the environment variable that names it. An unset switch leaves the framework as it ships.

Fields

a11y_sync: Diagnostic

CRANPOSE_A11Y_SYNC: Android publishes the accessibility tree on the UI thread (1) or off it (0).

ablate: Diagnostic

CRANPOSE_ABLATE: the comma-separated renderer stages to leave out.

adpf: Diagnostic

CRANPOSE_ADPF: 0 turns off Android’s performance hint session.

assert_state_chain: Diagnostic

CRANPOSE_ASSERT_STATE_CHAIN: checks every state record chain.

async_haptics: Diagnostic

CRANPOSE_ASYNC_HAPTICS: 0, false, off or no plays Android haptics on the calling thread.

background_pipelines: Diagnostic

CRANPOSE_BACKGROUND_PIPELINES: 0 or 1 turns compiling pipelines on background threads off or on.

compose_debug_modifiers: Diagnostic

COMPOSE_DEBUG_MODIFIERS: logs modifier chains.

compose_debug_slot_table: Diagnostic

COMPOSE_DEBUG_SLOT_TABLE: logs the slot table.

core_pin: Diagnostic

CRANPOSE_CORE_PIN: 0 keeps the render threads off the fast cores.

debug_scope_labels: Diagnostic

CRANPOSE_DEBUG_SCOPE_LABELS: labels recompose scopes in traces.

desktop_frame_telemetry: Diagnostic

CRANPOSE_DESKTOP_FRAME_TELEMETRY: logs desktop frames over the default threshold.

desktop_frame_telemetry_ms: Diagnostic

CRANPOSE_DESKTOP_FRAME_TELEMETRY_MS: logs desktop frames over this many milliseconds.

disable_nav_snap: Diagnostic

CRANPOSE_DISABLE_NAV_SNAP: the navigation bar does not snap.

disable_scroll_translate: Diagnostic

CRANPOSE_DISABLE_SCROLL_TRANSLATE: a scroll rebuilds its layers in place of moving them.

disable_structural_dirt: Diagnostic

CRANPOSE_DISABLE_STRUCTURAL_DIRT: the shell does not mark the parents of structural changes.

encode_delay_ms: Diagnostic

CRANPOSE_ENCODE_DELAY_MS: waits this many milliseconds before each frame’s encode on the present thread.

frame_lead_tenths: Diagnostic

CRANPOSE_FRAME_LEAD_TENTHS: pins the frame lead, in tenths of a frame period.

frame_stage_telemetry: Diagnostic

CRANPOSE_FRAME_STAGE_TELEMETRY: logs the shell’s frame stages over the default threshold.

frame_stage_telemetry_ms: Diagnostic

CRANPOSE_FRAME_STAGE_TELEMETRY_MS: logs the shell’s frame stages over this many milliseconds.

glass_material_folds: Diagnostic

CRANPOSE_GLASS_MATERIAL_FOLDS: 1 or 0 forces the glass material folds on or off.

gpu_fence_profile: Diagnostic

CRANPOSE_GPU_FENCE_PROFILE: profiles GPU fences.

gpu_pass_timing: Diagnostic

CRANPOSE_GPU_PASS_TIMING: times GPU passes with timestamp queries.

gpu_shadow_cache_diag: Diagnostic

CRANPOSE_GPU_SHADOW_CACHE_DIAG: logs the shadow cache.

gpu_stage_diag: Diagnostic

CRANPOSE_GPU_STAGE_DIAG: logs the renderer’s frame stages.

gpu_stats: Diagnostic

CRANPOSE_GPU_STATS: collects and prints the renderer’s frame stats.

layout_invalidation_dispatch_diag: Diagnostic

CRANPOSE_LAYOUT_INVALIDATION_DISPATCH_DIAG: logs layout invalidations (all for every one).

layout_measure_telemetry: Diagnostic

CRANPOSE_LAYOUT_MEASURE_TELEMETRY: logs measure passes over the default threshold.

layout_measure_telemetry_ms: Diagnostic

CRANPOSE_LAYOUT_MEASURE_TELEMETRY_MS: logs measure passes over this many milliseconds.

layout_repass_schedule_diag: Diagnostic

CRANPOSE_LAYOUT_REPASS_SCHEDULE_DIAG: logs layout repass scheduling (all for every one).

lazy_cache_telemetry: Diagnostic

CRANPOSE_LAZY_CACHE_TELEMETRY: logs the lazy list item cache.

lazy_item_telemetry: Diagnostic

CRANPOSE_LAZY_ITEM_TELEMETRY: logs lazy list item work.

lazy_measure_telemetry: Diagnostic

CRANPOSE_LAZY_MEASURE_TELEMETRY: logs lazy list measures.

location_key_diagnostics: Diagnostic

CRANPOSE_LOCATION_KEY_DIAGNOSTICS: logs location key collisions.

native_trace: Diagnostic

CRANPOSE_NATIVE_TRACE: prints native window events.

native_window_timing: Diagnostic

CRANPOSE_NATIVE_WINDOW_TIMING: prints native window timings.

no_backdrop_cache: Diagnostic

CRANPOSE_NO_BACKDROP_CACHE: draws backdrops without their cache.

no_effect_domains: Diagnostic

CRANPOSE_NO_EFFECT_DOMAINS: effects sample their whole sources.

no_fill_cache: Diagnostic

CRANPOSE_NO_FILL_CACHE: draws fills without the opaque prefix cache.

no_interiors_first: Diagnostic

CRANPOSE_NO_INTERIORS_FIRST: draws shape interiors in paint order.

no_shader_flatten: Diagnostic

CRANPOSE_NO_SHADER_FLATTEN: compiles shaders without flattening.

no_shader_fold: Diagnostic

CRANPOSE_NO_SHADER_FOLD: compiles shaders without folding constants.

no_shader_specialization: Diagnostic

CRANPOSE_NO_SHADER_SPECIALIZATION: draws with the general shaders.

pacing_diag: Diagnostic

CRANPOSE_PACING_DIAG: logs the desktop frame pacing.

pipeline_disk_cache: Diagnostic

CRANPOSE_PIPELINE_DISK_CACHE: 0 or 1 turns the pipeline disk cache off or on.

present_thread: Diagnostic

CRANPOSE_PRESENT_THREAD: chooses whether Android presents on a thread of its own.

probe_draw_passes: Diagnostic

CRANPOSE_PROBE_DRAW_PASSES: draws the first this many draw passes.

probe_passes: Diagnostic

CRANPOSE_PROBE_PASSES: encodes the first this many passes.

recompose_scope_telemetry_ms: Diagnostic

CRANPOSE_RECOMPOSE_SCOPE_TELEMETRY_MS: logs recompose scopes over this many milliseconds.

recomp_diag: Diagnostic

CRANPOSE_RECOMP_DIAG: prints the recomposition rate.

render_phase_dirty_diag: Diagnostic

CRANPOSE_RENDER_PHASE_DIRTY_DIAG: logs what the render phase finds dirty.

robot_button_helper_diag: Diagnostic

CRANPOSE_ROBOT_BUTTON_HELPER_DIAG: prints the robot’s button lookups.

scene_update_diag: Diagnostic

CRANPOSE_SCENE_UPDATE_DIAG: logs scene updates.

shape_variants: Diagnostic

CRANPOSE_SHAPE_VARIANTS: 0 draws shapes with the general pipeline.

skip_shadows: Diagnostic

CRANPOSE_SKIP_SHADOWS: leaves shadows out.

structural_diag: Diagnostic

CRANPOSE_STRUCTURAL_DIAG: logs structural child syncs.

subcompose_telemetry: Diagnostic

CRANPOSE_SUBCOMPOSE_TELEMETRY: logs subcompositions.

survive_gpu_errors: Diagnostic

CRANPOSE_SURVIVE_GPU_ERRORS: 0 stops on a GPU validation error.

text_atlas_fallback_diag: Diagnostic

CRANPOSE_TEXT_ATLAS_FALLBACK_DIAG: logs text that misses the glyph atlas.

text_layout_telemetry: Diagnostic

CRANPOSE_TEXT_LAYOUT_TELEMETRY: logs text layouts.

update_stage_telemetry_ms: Diagnostic

CRANPOSE_UPDATE_STAGE_TELEMETRY_MS: logs the shell’s update stages over this many milliseconds.

validate_slots: Diagnostic

CRANPOSE_VALIDATE_SLOTS: validates the slot table after each composition.

wgpu_render_stage_telemetry: Diagnostic

CRANPOSE_WGPU_RENDER_STAGE_TELEMETRY: logs the renderer’s stages over the default threshold.

wgpu_render_stage_telemetry_ms: Diagnostic

CRANPOSE_WGPU_RENDER_STAGE_TELEMETRY_MS: logs the renderer’s stages over this many milliseconds.