- r3d_open opens the window with nothing baked; r3d_load_count / r3d_load_step run the rest (sky
and light, terrain, shadow and screen targets, cover and actors, grass) so a game can present a
loading frame between them. r3d_init is the same calls in a row.
- sky_set_quality(width): the prefiltered sky light at 256 / 512 / 1024, baked again.
- post_set_msaa(samples): multisampling on OpenGL, remade in place (post_msaa_live is false on
Vulkan); post_free frees the multisampled framebuffer too.
- STREAM_BUDGET_US is a variable; r3d_fog_scale multiplies the fog the day sets.
- Vulkan buffers carry UNIFORM_BUFFER usage: the frame's ring is bound as uniform buffers and was
created without it (VUID-VkWriteDescriptorSet-descriptorType-00330, found on MoltenVK).
OpenGL frames at the five viewpoints unchanged; the game's 59 self-tests pass.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
- Device: multiDrawIndirect, drawIndirectFirstInstance and drawIndirectCount where present.
- Buffers carry storage and indirect usage; a GPU-owned buffer is never swapped under a draw.
- Compute programs from shaders/compute.list (binding 0 parameters, 1.. storage buffers),
built by `ludic-dev shaders`; gpu_compute / gpu_dispatch / gpu_draw_mesh_indirect in gpu.ludic.
- R3D_VK_PROBE=1: a dispatch read back (OK on the RTX 3070 Ti).
- scatter_cull.comp: a tree layer's frustum test and LOD split on the GPU, with the lit, prepass,
impostor and shadow-LOD draws reading its records. Behind R3D_GPU_CULL=1 and off by default:
at the camp it is slower (43.0 fps against 53.3), because the frame's cost is per-draw
descriptor sets and it adds empty-level draws. Validation-clean; OpenGL frames unchanged.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
R3D_VK_PROF at the camp view (about 2950 draws a frame) showed the frame spent in bookkeeping:
19.5 ms a frame finding pipelines by string key and 16 ms building descriptor sets.
- Pipelines: a mesh carries an interned vertex-layout id (dropped only when an attribute's shape
changes, not when an instance buffer is swapped), render state packs into an int and the pass
formats into another; the program's last hit is tried first. The string path only builds.
- Samplers: each texture keeps the sampler for its parameters until they change.
- Descriptor sets: a program's last set is reused within the frame while its blocks and resolved
textures are unchanged; a uniform write that repeats the value it already holds changes nothing.
Headless on the RTX 3070 Ti at 1920x1080: 21.7 -> 53.3 fps (pipelines 0.2 ms, sets 8.5 ms, inside
draws 10 ms a frame; OpenGL 114 fps). The camp frame is unchanged and validation-clean. OpenGL frames
byte-identical at the five viewpoints; 59 self-tests pass; VKRES OK.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
- A buffer re-uploaded after a draw this frame read it gets fresh storage, as OpenGL orphans
one; storage moved off or freed while the frame still reads it is destroyed after the frame's
submit. Draws mark the buffers they bind. No flush for buffer work.
- Mipmaps asked for mid-frame (the exposure measure, every frame) are recorded into the open frame
after its pass; growing a chain the first time keeps its one-shot path.
- R3D_VK_PROF prints, every 120 frames, draws and flushes per frame and the milliseconds spent
finding pipelines, filling descriptor sets and inside draws.
The gain was small - the camp view headless at 1920x1080 on the RTX 3070 Ti went from 21.3 to
21.7 fps (OpenGL: 114 fps) - so these flushes were not what holds the frame; the profile is how
the rest is found. The frame is unchanged and validation-clean; OpenGL frames byte-identical at the
five viewpoints with 59 self-tests passing.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Three things the first Vulkan frames on the RTX 3070 Ti showed against OpenGL on the same PC:
- Exposure: the adaptation pass reads the HDR scene's smallest mip, and a render target made
without pixels had one level, so exposure came from a single texel. A target asked for mipmaps
now grows a full chain (level 0 kept), and passes draw through level-0 views keyed by the
image's generation.
- Foliage: the depth prepass and the lit pass (depth EQUAL) are different variants. Vulkan vertex
stages now declare an invariant gl_Position so both land on the same depth.
- Alpha to coverage is enabled only on a multisampled pass. OpenGL ignores it without MSAA; Vulkan
with one sample dropped every fragment under half alpha.
vk_resources also checks a big-endian 16-bit RGB upload (a normal map). VKRES OK; ludic-dev test
140 passed; the PC's Vulkan frame is validation-clean; OpenGL frames byte-identical at the five
viewpoints with 59 self-tests passing.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
gpu.ludic's calls branch to the Vulkan backend when it was chosen and came up; every OpenGL
statement is unchanged, only guarded. R3D_GFX=vk selects it in a headless run (the window's
swapchain is the next milestone) and falls back to OpenGL, with the reason, when the device or
the SPIR-V manifest is missing.
- Render state is cached as before and turned into pipelines at the draw; u_* and sampler binds
go into the variant's uniform blocks; meshes, buffers and textures are gvk_* objects;
framebuffer binds are dynamic-rendering passes; same-size blits are image copies; the screen,
the photograph read-back, the present and the screenshot go through the frame.
- Work that submits on its own (uploads, read-backs, new or freed images and buffers) flushes the
frame first, so it runs in OpenGL's order. A read may take fewer channels than the image has
(the height field's R from its RGBA32F bake). Pipeline keys name vertex bindings by order, not
buffer handle, so re-pointed instance buffers keep their pipeline.
The valley renders at frame 90 validation-clean on the RTX 3070 Ti and on MoltenVK. OpenGL frames
byte-identical at the five viewpoints; 59 self-tests pass with no GL error.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The drawing half of the Vulkan backend, compiled into render3d and not yet reached from it:
- gvk_program: a program handle as its manifest variant - two SPIR-V modules, a descriptor set
layout (the vertex block at 0, the fragment block at 1, the samplers at their manifest bindings)
and a pipeline layout. Nothing is compiled at run time.
- gvk_pipeline: one pipeline per program, recorded vertex layout, render state and pass formats,
built the first time that combination draws. Attributes the shader does not read are left out;
the front face is clockwise, since neither API flips y between clip space and its target rows.
- gvk_uniform / gvk_u_set / gvk_bind_texture: loose uniforms written into each stage's block at
the manifest's offsets and array strides; gvk_draw_set copies the blocks into a per-frame ring
at the device's alignment and fills a descriptor set from a per-frame pool, with a white 1x1
texture for a sampler nothing was bound to.
- The frame: one command buffer; a framebuffer bind ends the pass and the next begins at its first
clear or draw (a clear that comes first is the load op); attachments move to attachment layouts
for the pass and back to SHADER_READ_ONLY after it, a cascade drawn through a view of its layer.
gvk_present submits and waits; gvk_screenshot reads the screen image back bottom row first.
r3d.ludic now imports gpu_manifest.ludic too. Textures remember their size.
OpenGL frames byte-identical at the five viewpoints; 59 self-tests pass; VKRES OK and VKDEVICE OK.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
gpu_vk_res.ludic gains what gpu.ludic's texture and buffer handles stand for on Vulkan:
- gvk_tex_storage / _upload / _mips / _read / _release: an image and view per handle, a full mip
chain when pixels come with it (the renderer asks for mipmaps after the upload) and one level
for a target, every level in SHADER_READ_ONLY between uses. Uploads are converted to what the
image stores: a missing alpha filled opaque (three-channel formats are stored with four), 16-bit
PNG samples byte-swapped when the unpack state says so, 32-bit float HDR halved into half
floats. Mips are blitted down level by level; a read-back brings level 0 home.
- gvk_sampler: one VkSampler per filter / wrap / compare / anisotropy combination, made when first
asked for, with GL's defaults where the renderer set nothing.
- gvk_buf_*: vertex, index and instance buffers behind one handle, kept when an upload fits.
Host-visible while the backend comes up.
gpu_vk.ludic switches on anisotropic sampling where the device has it and reads its limit.
examples/rendering/vk_resources.ludic checks it all: VKRES OK, validation-clean, every allocation
freed, on the RTX 3070 Ti (16x anisotropy) and on MoltenVK. One run on the Mac crashed while a
headless game run was using the GPU and did not come back in two reruns. OpenGL frames
byte-identical at the five viewpoints; 59 self-tests pass.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The Vulkan backend is two files. gpu_vk.ludic is the device, memory and one-shot commands,
pure Vulkan, and still runs on its own (vk_device.ludic). gpu_vk_res.ludic is the resources in
the renderer's vocabulary - OpenGL's names for formats, filters and blend factors, which only
exist where Gl.* is named - starting with the format table. r3d.ludic imports both after
gpu.ludic; nothing calls them yet.
OpenGL frames byte-identical at the five viewpoints; 59 self-tests pass; VKDEVICE OK.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
