render3d: free a texture's create infos and the .dds path it looked for; steady's model at 0

gvk_tex_storage freed none of ici, out, req and vci (8 blocks a two-texture model); tex_load_ex kept
dds_path_of's string. Found with malloc_history over 400 load/release rounds (712 bytes a round, all
of it these). steady: the model's bound is 4 KB over 200 (was 1.6 MB), and the frame is the least of
three settled windows - a valley self-test beside it read 87 KB once.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

changes/render3d-texture-scratch.md

@@ -0,0 +1,7 @@
+bump: patch
+type: fix
+**A texture made and freed leaves nothing behind.** Making a texture's image once kept four small
+Vulkan create-info buffers, and a texture loaded from a .png kept the .dds path it looked for
+beside it; both are given back now. `examples/rendering/steady.ludic` holds a glTF model loaded and
+released at 0 bytes, and reads a frame's growth as the least of three windows after the device is
+idle, so a busy machine beside it does not fail it.

examples/rendering/steady.ludic

@@ -1,7 +1,7 @@
 # steady.ludic - render3d allocates nothing in its steady state: a buffer released and made again
 # (what a streamed or grown buffer does every few frames) and a whole frame, drawn over and over,
 # leave malloc's live bytes where they were. Prints STEADY OK. The heap is read on the Mac
-# (Vk.heap_bytes); elsewhere it reads 0 and the check passes on the run alone.
+# (Vk.heap_bytes) once the device is idle; elsewhere it reads 0 and the check passes on the run alone.
 #
 #   bin/ludic build examples/rendering/steady.ludic --headless && ./build/steady_headless
 program Steady {
@@ -95,7 +95,13 @@ program Steady {
     buffer_rounds(render3d_st, b, 500)
     let grew_b = buffer_rounds(render3d_st, b, 5000)
     frame_rounds(render3d_st, 120)
-    let grew_f = frame_rounds(render3d_st, 600)
+    # the least of three windows: a leak grows in every one, while a busy GPU's lag (a valley
+    # self-test beside it once read 87 KB) does not repeat three times
+    var grew_f = frame_rounds(render3d_st, 600)
+    for w in 0 .. 2 {
+      let g = frame_rounds(render3d_st, 600)
+      if g < grew_f { grew_f = g }
+    }
     model_rounds(render3d_st, 20)
     let grew_m = model_rounds(render3d_st, 200)
     let am = gltf_load(render3d_st, "packages/ludic.lab/plate", "plate.gltf", "plate")
@@ -116,9 +122,9 @@ program Steady {
       ok = false
       print("steady: FAILED - a parsed document freed whole leaves memory behind")
     }
-    # a load keeps a few records of its own for now (handles are not reused); a document's strings
-    # left behind were ~640 KB a model, so a bound of 8 KB a round is what this holds
-    if grew_m >= 200 * 8192 {
+    # a load and a release leave nothing: 0 over 200 (a document's strings were ~640 KB a model, a
+    # texture's create infos and its .dds path ~700 bytes a round)
+    if grew_m >= 4096 {
       ok = false
       print("steady: FAILED - a model loaded and let go leaves memory behind")
     }

packages/ludic.render3d/gpu_vk_res.ludic

@@ -212,11 +212,18 @@ function gvk_tex_storage(render3d_st: mut Render3dState, tex: int, array: bool,
   let out = bytes(8)
   render3d_st.gvk_mk_img += 1
   var r = Vk.create_image(render3d_st.gvk_dev, ici, null, out)
-  if r != VK_SUCCESS { return gvk_fail(render3d_st, `vkCreateImage {w}x{h}x{layers} format {vkfmt}`, r) }
+  # the create infos are read by the call they are handed to and go straight after (a texture
+  # made in play once left four of them behind)
+  free(ici)
+  if r != VK_SUCCESS {
+    free(out)
+    return gvk_fail(render3d_st, `vkCreateImage {w}x{h}x{layers} format {vkfmt}`, r)
+  }
   let image = gvk_handle(out)
   let req = bytes(VkMemoryRequirements_sizeof)
   Vk.get_image_memory_requirements(render3d_st.gvk_dev, image, req)
   let ma = gvk_mem_new(render3d_st, req, VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT, true)
+  free(req)
   let mem: long = ma                    # the allocation id (gvk_mem_new), kept where the memory was
   let zero: long = 0
   # no memory for it (one allocation per resource meets the driver's allocation limit long before
@@ -224,10 +231,14 @@ function gvk_tex_storage(render3d_st: mut Render3dState, tex: int, array: bool,
   if mem == 0 {
     render3d_st.gvk_mk_x_img += 1
     Vk.destroy_image(render3d_st.gvk_dev, image, null)
+    free(out)
     return gvk_fail(render3d_st, `no device memory for a {w}x{h}x{layers} image ({render3d_st.gvk_n_allocs} allocations live)`, VK_ERROR_OUT_OF_DEVICE_MEMORY)
   }
   r = Vk.bind_image_memory(render3d_st.gvk_dev, image, gvk_mem_handle(render3d_st, ma), gvk_mem_offset(render3d_st, ma))
-  if r != VK_SUCCESS { return gvk_fail(render3d_st, "vkBindImageMemory", r) }
+  if r != VK_SUCCESS {
+    free(out)
+    return gvk_fail(render3d_st, "vkBindImageMemory", r)
+  }
   let vci = bytes(VkImageViewCreateInfo_sizeof)
   Vk.zero(vci, VkImageViewCreateInfo_sizeof)
   Vk.put_i32(vci, VkImageViewCreateInfo_sType, VK_STRUCTURE_TYPE_IMAGE_VIEW_CREATE_INFO)
@@ -240,8 +251,11 @@ function gvk_tex_storage(render3d_st: mut Render3dState, tex: int, array: bool,
   Vk.put_i32(vci, sr + VkImageSubresourceRange_layerCount, layers)
   render3d_st.gvk_mk_view += 1
   r = Vk.create_image_view(render3d_st.gvk_dev, vci, null, out)
+  free(vci)
+  let view = gvk_handle(out)
+  free(out)
   if r != VK_SUCCESS { return gvk_fail(render3d_st, "vkCreateImageView", r) }
-  render3d_st.gvk_tex_image[tex] = image;  render3d_st.gvk_tex_view[tex] = gvk_handle(out);  render3d_st.gvk_tex_mem[tex] = mem
+  render3d_st.gvk_tex_image[tex] = image;  render3d_st.gvk_tex_view[tex] = view;  render3d_st.gvk_tex_mem[tex] = mem
   render3d_st.gvk_tex_levels[tex] = levels;  render3d_st.gvk_tex_layers[tex] = layers;  render3d_st.gvk_tex_vkfmt[tex] = vkfmt
   render3d_st.gvk_tex_dims_w[tex] = w;  render3d_st.gvk_tex_dims_h[tex] = h
   render3d_st.gvk_tex_glfmt[tex] = ifmt;  render3d_st.gvk_tex_gen[tex] = render3d_st.gvk_tex_gen[tex] + 1

packages/ludic.render3d/texture.ludic

@@ -267,12 +267,14 @@ function tex_load_ex(render3d_st: mut Render3dState, path: pointer, srgb: bool,
   # (not for a cut-out atlas: its edge padding is made here, from the .png)
   if render3d_st.gvk_has_bc and dilate == 0 {
     let dds = dds_path_of(path)
-    if len(dds) > 0 and Fs.exists(dds) {
-      let t = tex_load_dds(render3d_st, dds, srgb)
-      if t != 0 {
-        tex_note_size(render3d_st, t)
-        return t
-      }
+    var t = 0
+    if len(dds) > 0 {
+      if Fs.exists(dds) { t = tex_load_dds(render3d_st, dds, srgb) }
+      free(dds)                                 # made for this question ("" is a literal)
+    }
+    if t != 0 {
+      tex_note_size(render3d_st, t)
+      return t
     }
   }
   let px = png_decode(render3d_st, path)