Preallocate texture VRAM, move files around

src/Chunk.zig

@@ -1,19 +1,19 @@
 const Chunk = @This();
 const std = @import("std");
 
-const ctx = @import("../AppContext.zig");
+const ctx = @import("AppContext.zig");
-const math = @import("../math.zig");
+const math = @import("math.zig");
-const shaders = @import("../shaders.zig");
+const shaders = @import("shaders.zig");
 const vk = @import("vulkan");
 const vm = @import("vecmath");
-const voxels = @import("../voxels.zig");
+const voxels = @import("voxels.zig");
 
-const Blocks = @import("Blocks.zig");
+const Blocks = @import("assets/Blocks.zig");
-const CommandBuffer = @import("../engine/CommandBuffer.zig");
+const CommandBuffer = @import("engine/CommandBuffer.zig");
-const Engine = @import("../engine/Engine.zig");
+const Engine = @import("engine/Engine.zig");
-const Game = @import("../Game.zig");
+const Game = @import("Game.zig");
-const GenericBuffer = @import("../engine/GenericBuffer.zig").GenericBuffer;
+const GenericBuffer = @import("engine/GenericBuffer.zig").GenericBuffer;
-const Materials = @import("Materials.zig");
+const Materials = @import("engine/Materials.zig");
 
 const ObjectUniformsBuffer = GenericBuffer(void, shaders.ObjectUniforms);
 

src/Chunks.zig

@@ -9,7 +9,7 @@ const vm = @import("vecmath");
 const voxels = @import("voxels.zig");
 
 const Blocks = @import("assets/Blocks.zig");
-const Chunk = @import("assets/Chunk.zig");
+const Chunk = @import("Chunk.zig");
 const Engine = @import("engine/Engine.zig");
 const Iterator2 = math.Iterator2;
 

src/Game.zig

@@ -12,19 +12,19 @@ const vm = @import("vecmath");
 const worldgen = @import("worldgen.zig");
 
 const Blocks = @import("assets/Blocks.zig");
-const Chunk = @import("assets/Chunk.zig");
+const Chunk = @import("Chunk.zig");
 const Chunks = @import("Chunks.zig");
 const CommandBuffer = @import("engine/CommandBuffer.zig");
 const Engine = @import("engine/Engine.zig");
 const Gui = @import("Gui.zig");
 const Iterator2 = math.Iterator2;
-const Materials = @import("assets/Materials.zig");
+const Materials = @import("engine/Materials.zig");
 const Player = @import("Player.zig");
 const Skybox = @import("engine/Skybox.zig");
 const StagingBuffer = @import("engine/StagingBuffer.zig");
 const Swapchain = @import("engine/Swapchain.zig");
 const Texture = @import("engine/Texture.zig");
-const Textures = @import("assets/Textures.zig");
+const Textures = @import("engine/Textures.zig");
 
 global_descriptor_set_layout: vk.DescriptorSetLayout,
 per_batch_descriptor_set_layout: vk.DescriptorSetLayout,
@@ -899,7 +899,7 @@ fn render(self: *Game) !void {
 
     try command_buffer.beginCommandBuffer();
     {
-        const swapchain_image = &swapchain.swapchain_images[swapchain.image_index.?];
+        const swapchain_image = swapchain.getCurrentSwapchainImage();
 
         command_buffer.pipelineBarrier(.{
             .src_stage_mask = .{ .color_attachment_output_bit = true },
@@ -988,31 +988,25 @@ fn render(self: *Game) !void {
             },
         });
 
-        command_buffer.setViewport(0, &.{
+        command_buffer.setViewport(0, .{
-            .{
             .x = 0,
             .y = 0,
             .width = @floatFromInt(extent.width),
             .height = @floatFromInt(extent.height),
             .min_depth = 0,
             .max_depth = 1,
-            },
         });
-        command_buffer.setScissor(0, &.{
+        command_buffer.setScissor(0, .{
-            .{
             .offset = .{ .x = 0, .y = 0 },
             .extent = extent,
-            },
         });
 
         // --- RENDER 3D SCENE ---
 
         command_buffer.bindPipeline(.graphics, self.pipeline);
-        try command_buffer.bindVertexBuffers(0, &.{
+        try command_buffer.bindVertexBuffer(0, .{
-            .{
             .buffer = self.vertex_buffer.buffer,
             .offset = 0,
-            },
         });
         command_buffer.bindIndexBuffer(self.index_buffer.buffer, 0, .uint16);
         command_buffer.bindDescriptorSet(.graphics, self.pipeline_layout, 0, self.global_descriptor_set, null);

src/Gui.zig

@@ -11,7 +11,7 @@ const Engine = @import("engine/Engine.zig");
 const GenericBuffer = @import("engine/GenericBuffer.zig").GenericBuffer;
 const Swapchain = @import("engine/Swapchain.zig");
 const Texture = @import("engine/Texture.zig");
-const Textures = @import("assets/Textures.zig");
+const Textures = @import("engine/Textures.zig");
 
 pub const Draw = struct {
     pub const Box = extern struct {

src/assets/Blocks.zig

@@ -9,8 +9,8 @@ const voxels = @import("../voxels.zig");
 
 const Atom = @import("../engine/Atom.zig").Atom;
 const Engine = @import("../engine/Engine.zig");
-const Materials = @import("Materials.zig");
+const Materials = @import("../engine/Materials.zig");
-const Textures = @import("Textures.zig");
+const Textures = @import("../engine/Textures.zig");
 
 pub const Id = enum(u16) {
     // VOLATILE Synchronize explicit values with `init` implementation.

src/engine/Atom.zig

@@ -2,8 +2,13 @@ const std = @import("std");
 
 const ctx = @import("../AppContext.zig");
 
+/// Interned string ID. A string can be converted to a stable integer constant,
+/// called an *atom*. The value of an atom for a given string is guaranteed to
+/// be stable throughout a program's runtime, but not across different runs.
+/// There can be no more than 2¹⁶ atoms.
 pub const Atom = enum(u16) {
-    // VOLATILE Synchronize explicit values with `Atoms.init` implementation.
+    // VOLATILE When modifying the list of explicitly defined atoms (i.e. any
+    // explicit enum value), we need to update `Atoms.init` implementation.
 
     /// Atom representing an empty string, i.e. `""`.
     empty,

src/engine/Atoms.zig

@@ -3,13 +3,13 @@
 //! guaranteed to be stable throughout a program's runtime, but not across
 //! different runs. There can be no more than 2¹⁶ atoms.
 //!
-//! Use this module to convert string IDs into numbers, so that they can be
+//! The users should instead import `@import("Atom.zig").Atom` and use the
-//! compared more easily. The users of this module should instead import
+//! methods available in the `Atom` type instead of accessing this module
-//! `@import("Atom.zig").Atom` and use the methods available in the `Atom` type.
+//! directly.
 //!
-//! This module is intended to be initialized once and persist until the end of
+//! This module is intended to be initialized once and to persist until the end
-//! the whole application. Trying to use it in any other way will result in
+//! of the whole program's runtime. Trying to use it in any other way will
-//! weird behavior.
+//! result in weird behavior.
 
 const Atoms = @This();
 const std = @import("std");
@@ -40,7 +40,9 @@ pub fn init() !*Atoms {
         .mutex = .init,
     };
 
-    // VOLATILE Synchronize with explicit values on top of `Atom` type.
+    // VOLATILE The initial contents of `atoms.map` and `atoms.array` must
+    // correspond to explicitly defined values at the top of the `Atom` type.
+
     try atoms.map.put(allocator_general, "", .empty);
     try atoms.array.append(allocator_general, "");
 
@@ -49,18 +51,14 @@ pub fn init() !*Atoms {
 
 pub fn deinit(self: *Atoms) void {
     const allocator_general = ctx.allocator_general;
-    const io = ctx.io;
-
-    {
-        // VOLATILE Unlock mutex before `self.* = undefined` line.
-        self.mutex.lockUncancelable(io);
-        defer self.mutex.unlock(io);
 
     std.log.scoped(.deinit).debug("Deinitializing {*}", .{self});
 
+    // No waiting; if atoms are in use while deinitializing, something is wrong.
+    std.debug.assert(self.mutex.tryLock());
+
     self.map.deinit(allocator_general);
     self.array.deinit(allocator_general);
-    }
 
     self.* = undefined;
 }

src/engine/CommandBuffer.zig

@@ -21,10 +21,7 @@ queue_type: QueueType,
 pub fn init(queue_type: QueueType) !CommandBuffer {
     const engine = ctx.engine;
 
-    const handle = try engine.allocateCommandBuffer(.{
+    const handle = try engine.allocateCommandBuffer(.{ .queue_type = queue_type });
-        .queue_type = queue_type,
-        .level = .primary,
-    });
     return .{
         .proxy = .init(handle, engine.device.wrapper),
         .queue_type = queue_type,
@@ -49,6 +46,40 @@ pub fn submit(self: CommandBuffer, submit_info: Engine.SubmitInfo) !void {
 
 // --- VULKAN WRAPPERS ---------------------------------------------------------
 
+fn ToVkType(comptime T: type) type {
+    if (!std.meta.hasFn(T, "toVk")) {
+        @compileError("Type " ++ T ++ " has no toVk method.");
+    }
+
+    const to_vk_type_info = @typeInfo(@TypeOf(@field(T, "toVk")));
+    return to_vk_type_info.@"fn".return_type.?;
+}
+
+fn toVkOptional(comptime T: type, maybe_value: ?T) !?*const ToVkType(T) {
+    const allocator_frame = ctx.allocator_frame;
+
+    if (maybe_value) |value| {
+        const ptr = try allocator_frame.create(ToVkType(T));
+        if (std.meta.hasFn(T, "toVk")) {
+            ptr.* = value.toVk();
+        }
+        return ptr;
+    } else {
+        return null;
+    }
+}
+
+fn toVkMulti(comptime T: type, values: []const T) ![*]const ToVkType(T) {
+    const allocator_frame = ctx.allocator_frame;
+
+    const slice = try allocator_frame.alloc(ToVkType(T), values.len);
+    for (slice, values) |*y, x| {
+        y.* = x.toVk();
+    }
+
+    return slice.ptr;
+}
+
 pub const DrawIndexed = struct {
     index_count: u32,
     instance_count: u32 = 1,
@@ -75,6 +106,19 @@ pub const RenderingAttachmentInfo = struct {
     load_op: vk.AttachmentLoadOp,
     store_op: vk.AttachmentStoreOp,
     clear_value: vk.ClearValue,
+
+    pub fn toVk(self: RenderingAttachmentInfo) vk.RenderingAttachmentInfo {
+        return .{
+            .image_view = self.image_view,
+            .image_layout = self.image_layout,
+            .resolve_mode = self.resolve_mode,
+            .resolve_image_view = self.resolve_image_view,
+            .resolve_image_layout = self.resolve_image_layout,
+            .load_op = self.load_op,
+            .store_op = self.store_op,
+            .clear_value = self.clear_value,
+        };
+    }
 };
 
 pub const RenderingInfo = struct {
@@ -85,11 +129,40 @@ pub const RenderingInfo = struct {
     color_attachments: []const RenderingAttachmentInfo = &.{},
     depth_attachment: ?RenderingAttachmentInfo = null,
     stencil_attachment: ?RenderingAttachmentInfo = null,
+
+    pub fn toVk(self: RenderingInfo) !vk.RenderingInfo {
+        return .{
+            .flags = self.flags,
+            .render_area = self.render_area,
+            .layer_count = self.layer_count,
+            .view_mask = self.view_mask,
+            .color_attachment_count = @intCast(self.color_attachments.len),
+            .p_color_attachments = try toVkMulti(RenderingAttachmentInfo, self.color_attachments),
+            .p_depth_attachment = try toVkOptional(RenderingAttachmentInfo, self.depth_attachment),
+            .p_stencil_attachment = try toVkOptional(RenderingAttachmentInfo, self.stencil_attachment),
+        };
+    }
 };
 
 pub const VertexBufferBinding = struct {
     buffer: vk.Buffer,
     offset: usize,
+
+    pub fn transpose(vertex_buffer_bindings: []const VertexBufferBinding) !struct { []const vk.Buffer, []const usize } {
+        const allocator_frame = ctx.allocator_frame;
+
+        var t: std.MultiArrayList(VertexBufferBinding) = .empty;
+        try t.ensureTotalCapacity(allocator_frame, vertex_buffer_bindings.len);
+
+        for (vertex_buffer_bindings) |binding| {
+            t.appendAssumeCapacity(binding);
+        }
+
+        return .{
+            t.items(.buffer),
+            t.items(.offset),
+        };
+    }
 };
 
 pub fn beginCommandBuffer(self: CommandBuffer) !void {
@@ -101,50 +174,8 @@ pub fn beginCommandBuffer(self: CommandBuffer) !void {
 }
 
 pub fn beginRendering(self: CommandBuffer, rendering_info: RenderingInfo) !void {
-    const allocator_frame = ctx.allocator_frame;
+    const rendering_info_vk = try rendering_info.toVk();
-
+    self.proxy.beginRendering(&rendering_info_vk);
-    const color_attachments = try allocator_frame.alloc(vk.RenderingAttachmentInfo, rendering_info.color_attachments.len);
-    for (color_attachments, rendering_info.color_attachments) |*x, color_attachment| {
-        x.* = .{
-            .image_view = color_attachment.image_view,
-            .image_layout = color_attachment.image_layout,
-            .resolve_mode = color_attachment.resolve_mode,
-            .resolve_image_view = color_attachment.resolve_image_view,
-            .resolve_image_layout = color_attachment.resolve_image_layout,
-            .load_op = color_attachment.load_op,
-            .store_op = color_attachment.store_op,
-            .clear_value = color_attachment.clear_value,
-        };
-    }
-
-    self.proxy.beginRendering(&.{
-        .flags = rendering_info.flags,
-        .render_area = rendering_info.render_area,
-        .layer_count = rendering_info.layer_count,
-        .view_mask = rendering_info.view_mask,
-        .color_attachment_count = @intCast(color_attachments.len),
-        .p_color_attachments = color_attachments.ptr,
-        .p_depth_attachment = if (rendering_info.depth_attachment) |x| &.{
-            .image_view = x.image_view,
-            .image_layout = x.image_layout,
-            .resolve_mode = x.resolve_mode,
-            .resolve_image_view = x.resolve_image_view,
-            .resolve_image_layout = x.resolve_image_layout,
-            .load_op = x.load_op,
-            .store_op = x.store_op,
-            .clear_value = x.clear_value,
-        } else null,
-        .p_stencil_attachment = if (rendering_info.stencil_attachment) |x| &.{
-            .image_view = x.image_view,
-            .image_layout = x.image_layout,
-            .resolve_mode = x.resolve_mode,
-            .resolve_image_view = x.resolve_image_view,
-            .resolve_image_layout = x.resolve_image_layout,
-            .load_op = x.load_op,
-            .store_op = x.store_op,
-            .clear_value = x.clear_value,
-        } else null,
-    });
 }
 
 pub fn bindDescriptorSet(
@@ -181,48 +212,21 @@ pub fn bindDescriptorSets(
     );
 }
 
-pub fn bindPipeline(self: CommandBuffer, pipeline_bind_point: vk.PipelineBindPoint, pipeline: vk.Pipeline) void {
-    self.proxy.bindPipeline(pipeline_bind_point, pipeline);
-}
-
 pub fn bindIndexBuffer(self: CommandBuffer, buffer: vk.Buffer, offset: u64, index_type: vk.IndexType) void {
     self.proxy.bindIndexBuffer(buffer, offset, index_type);
 }
 
+pub fn bindPipeline(self: CommandBuffer, pipeline_bind_point: vk.PipelineBindPoint, pipeline: vk.Pipeline) void {
+    self.proxy.bindPipeline(pipeline_bind_point, pipeline);
+}
+
+pub fn bindVertexBuffer(self: CommandBuffer, index: u32, binding: VertexBufferBinding) !void {
+    self.proxy.bindVertexBuffers(index, &.{binding.buffer}, &.{binding.offset});
+}
+
 pub fn bindVertexBuffers(self: CommandBuffer, first_binding: u32, bindings: []const VertexBufferBinding) !void {
-    const allocator_frame = ctx.allocator_frame;
+    const buffers, const offsets = try VertexBufferBinding.transpose(bindings);
-
+    self.proxy.bindVertexBuffers(first_binding, buffers, offsets);
-    var vertex_buffer_bindings = std.MultiArrayList(VertexBufferBinding){};
-    defer vertex_buffer_bindings.deinit(allocator_frame);
-    try vertex_buffer_bindings.ensureTotalCapacity(allocator_frame, bindings.len);
-
-    for (bindings) |binding| {
-        vertex_buffer_bindings.appendAssumeCapacity(binding);
-    }
-
-    self.proxy.bindVertexBuffers(
-        first_binding,
-        vertex_buffer_bindings.items(.buffer),
-        vertex_buffer_bindings.items(.offset),
-    );
-}
-
-pub fn drawIndexed(self: CommandBuffer, draw_indexed: DrawIndexed) void {
-    self.proxy.drawIndexed(
-        draw_indexed.index_count,
-        draw_indexed.instance_count,
-        draw_indexed.first_index,
-        draw_indexed.vertex_offset,
-        draw_indexed.first_instance,
-    );
-}
-
-pub fn endCommandBuffer(self: CommandBuffer) !void {
-    try self.proxy.endCommandBuffer();
-}
-
-pub fn endRendering(self: CommandBuffer) void {
-    self.proxy.endRendering();
 }
 
 pub fn copyBuffer(
@@ -244,8 +248,22 @@ pub fn copyBufferToImage(
     self.proxy.copyBufferToImage(src_buffer, dst_image, dst_image_layout, regions);
 }
 
-pub fn nextSubpass(self: CommandBuffer, contents: vk.SubpassContents) void {
+pub fn drawIndexed(self: CommandBuffer, draw_indexed: DrawIndexed) void {
-    self.proxy.nextSubpass(contents);
+    self.proxy.drawIndexed(
+        draw_indexed.index_count,
+        draw_indexed.instance_count,
+        draw_indexed.first_index,
+        draw_indexed.vertex_offset,
+        draw_indexed.first_instance,
+    );
+}
+
+pub fn endCommandBuffer(self: CommandBuffer) !void {
+    try self.proxy.endCommandBuffer();
+}
+
+pub fn endRendering(self: CommandBuffer) void {
+    self.proxy.endRendering();
 }
 
 pub fn pipelineBarrier(self: CommandBuffer, barrier: PipelineBarrier) void {
@@ -259,10 +277,18 @@ pub fn pipelineBarrier(self: CommandBuffer, barrier: PipelineBarrier) void {
     );
 }
 
-pub fn setScissor(self: CommandBuffer, first_scissor: u32, scissors: []const vk.Rect2D) void {
+pub fn setScissor(self: CommandBuffer, index: u32, scissor: vk.Rect2D) void {
+    self.proxy.setScissor(index, &.{scissor});
+}
+
+pub fn setScissors(self: CommandBuffer, first_scissor: u32, scissors: []const vk.Rect2D) void {
     self.proxy.setScissor(first_scissor, scissors);
 }
 
-pub fn setViewport(self: CommandBuffer, first_viewport: u32, viewports: []const vk.Viewport) void {
+pub fn setViewport(self: CommandBuffer, index: u32, viewports: vk.Viewport) void {
+    self.proxy.setViewport(index, &.{viewports});
+}
+
+pub fn setViewports(self: CommandBuffer, first_viewport: u32, viewports: []const vk.Viewport) void {
     self.proxy.setViewport(first_viewport, viewports);
 }

src/engine/DeviceAllocation.zig

@@ -0,0 +1,53 @@
+const std = @import("std");
+const DeviceAllocation = @This();
+
+const ctx = @import("../AppContext.zig");
+const vk = @import("vulkan");
+
+device_memory: vk.DeviceMemory,
+memory_type_index: u32,
+allocated: usize,
+capacity: usize,
+
+pub fn deinit(self: *DeviceAllocation) void {
+    const engine = ctx.engine;
+
+    engine.freeMemory(self.device_memory);
+    self.* = undefined;
+}
+
+pub fn bindBuffer(self: *DeviceAllocation, buffer: vk.Buffer) !void {
+    const engine = ctx.engine;
+
+    const memory_requirements = engine.getBufferMemoryRequirements(buffer);
+    const is_type = memory_requirements.memory_type_bits & (@as(u32, 1) << @truncate(self.memory_type_index)) != 0;
+    std.debug.assert(is_type);
+
+    const offset = std.mem.alignForward(usize, self.allocated, memory_requirements.alignment);
+    const next_allocated = offset + memory_requirements.size;
+
+    if (next_allocated > self.capacity) {
+        return error.OutOfMemory;
+    }
+
+    try engine.bindBufferMemory(buffer, self.device_memory, offset);
+    self.allocated = next_allocated;
+}
+
+pub fn bindImage(self: *DeviceAllocation, image: vk.Image) !void {
+    const engine = ctx.engine;
+
+    const memory_requirements = engine.getImageMemoryRequirements(image);
+    const is_type = memory_requirements.memory_type_bits & (@as(u32, 1) << @truncate(self.memory_type_index)) != 0;
+    std.debug.assert(is_type);
+
+    const offset = std.mem.alignForward(usize, self.allocated, memory_requirements.alignment);
+    const next_allocated = offset + memory_requirements.size;
+
+    if (next_allocated > self.capacity) {
+        return error.OutOfMemory;
+    }
+
+    try engine.bindImageMemory(image, self.device_memory, offset);
+    self.allocated = next_allocated;
+}

src/engine/Engine.zig

@@ -6,6 +6,7 @@ const ctx = @import("../AppContext.zig");
 const glfw = @import("zglfw");
 const vk = @import("vulkan");
 
+const DeviceAllocation = @import("DeviceAllocation.zig");
 const Queue = @import("Queue.zig");
 const QueueType = @import("QueueType.zig").QueueType;
 const VkAllocator = @import("VkAllocator.zig");
@@ -418,18 +419,46 @@ pub fn deinit(self: *Engine) void {
 }
 
 pub fn allocate(self: *const Engine, memory_requirements: vk.MemoryRequirements, memory_property_flags: vk.MemoryPropertyFlags) !vk.DeviceMemory {
-    for (self.memory_types.items, 0..) |memory_type, i| {
+    const memory_type_index = try self.findMemoryTypeIndex(memory_requirements.memory_type_bits, memory_property_flags);
-        const is_type = memory_requirements.memory_type_bits & (@as(u32, 1) << @truncate(i)) != 0;
+
-        const has_flags = memory_type.property_flags.contains(memory_property_flags);
+    return self.device.allocateMemory(&.{
-        if (is_type and has_flags) {
-            return try self.device.allocateMemory(&.{
         .allocation_size = memory_requirements.size,
-                .memory_type_index = @truncate(i),
+        .memory_type_index = memory_type_index,
     }, ctx.vk_allocator.capture());
 }
-    }
 
-    return error.NoSuitableMemoryType;
+/// Allocate `vk.DeviceMemory` suitable for image created by given
+/// `create_info`, except the allocation is `size` bytes large.
+pub fn allocateForImage(
+    self: *const Engine,
+    create_info: ImageCreateInfo,
+    plane_aspect: vk.ImageAspectFlags,
+    size: usize,
+    memory_property_flags: vk.MemoryPropertyFlags,
+) !DeviceAllocation {
+    const create_info_vk = try create_info.toVk();
+
+    var memory_requirements2: vk.MemoryRequirements2 = .{
+        .memory_requirements = undefined,
+    };
+    self.device.getDeviceImageMemoryRequirements(&.{
+        .p_create_info = &create_info_vk,
+        .plane_aspect = plane_aspect,
+    }, &memory_requirements2);
+
+    const memory_requirements = memory_requirements2.memory_requirements;
+    const memory_type_index = try self.findMemoryTypeIndex(memory_requirements.memory_type_bits, memory_property_flags);
+    const device_memory = try self.device.allocateMemory(&.{
+        .allocation_size = size,
+        .memory_type_index = memory_type_index,
+    }, ctx.vk_allocator.capture());
+
+    return .{
+        .device_memory = device_memory,
+        .allocated = 0,
+        .capacity = size,
+        .memory_type_index = memory_type_index,
+    };
 }
 
 pub fn setObjectName(self: *const Engine, handle: anytype, comptime fmt: []const u8, args: anytype) void {
@@ -663,8 +692,16 @@ fn findPresentationQueueFamily(queue_families_properties: []const vk.QueueFamily
     return null;
 }
 
-fn makeArena(self: *const Engine) std.heap.ArenaAllocator {
+fn findMemoryTypeIndex(self: *const Engine, memory_type_bits: u32, memory_property_flags: vk.MemoryPropertyFlags) !u32 {
-    return .init(self.vk_allocator.allocator);
+    for (self.memory_types.items, 0..) |memory_type, i| {
+        const is_type = memory_type_bits & (@as(u32, 1) << @truncate(i)) != 0;
+        const has_flags = memory_type.property_flags.contains(memory_property_flags);
+        if (is_type and has_flags) {
+            return @truncate(i);
+        }
+    }
+
+    return error.NoSuitableMemoryType;
 }
 
 fn resolveCommandPool(self: *const Engine, queue_type: QueueType) vk.CommandPool {
@@ -692,7 +729,7 @@ pub const BufferCreateInfo = struct {
 
 pub const CommandBufferAllocateInfo = struct {
     queue_type: QueueType,
-    level: vk.CommandBufferLevel,
+    level: vk.CommandBufferLevel = .primary,
 };
 
 pub const CommandBufferFreeInfo = struct {
@@ -769,6 +806,33 @@ pub const ImageCreateInfo = struct {
     usage: vk.ImageUsageFlags,
     queue_family_indices: []const u32 = &.{},
     initial_layout: vk.ImageLayout,
+
+    pub fn toVk(self: ImageCreateInfo) !vk.ImageCreateInfo {
+        const allocator_frame = ctx.allocator_frame;
+
+        var queue_family_indices_set: std.AutoArrayHashMapUnmanaged(u32, void) = .{};
+        for (self.queue_family_indices) |queue_family_index| {
+            try queue_family_indices_set.put(allocator_frame, queue_family_index, {});
+        }
+
+        const queue_family_indices = queue_family_indices_set.keys();
+
+        return .{
+            .flags = self.flags,
+            .image_type = self.image_type,
+            .format = self.format,
+            .extent = self.extent,
+            .mip_levels = self.mip_levels,
+            .array_layers = self.array_layers,
+            .samples = self.samples,
+            .tiling = self.tiling,
+            .usage = self.usage,
+            .sharing_mode = if (queue_family_indices.len > 1) .concurrent else .exclusive,
+            .queue_family_index_count = if (queue_family_indices.len > 1) @intCast(queue_family_indices.len) else 0,
+            .p_queue_family_indices = if (queue_family_indices.len > 1) queue_family_indices.ptr else null,
+            .initial_layout = self.initial_layout,
+        };
+    }
 };
 
 pub const ImageViewCreateInfo = struct {
@@ -1110,31 +1174,8 @@ pub fn createGraphicsPipeline(self: *Engine, create_info: GraphicsPipelineCreate
 }
 
 pub fn createImage(self: *Engine, create_info: ImageCreateInfo) !vk.Image {
-    const allocator_frame = ctx.allocator_frame;
+    const create_info_vk = try create_info.toVk();
-
+    return self.device.createImage(&create_info_vk, ctx.vk_allocator.capture());
-    var queue_family_indices_set: std.AutoArrayHashMapUnmanaged(u32, void) = .{};
-    for (create_info.queue_family_indices) |queue_family_index| {
-        try queue_family_indices_set.put(allocator_frame, queue_family_index, {});
-    }
-
-    const queue_family_indices = queue_family_indices_set.keys();
-
-    const image = self.device.createImage(&.{
-        .flags = create_info.flags,
-        .image_type = create_info.image_type,
-        .format = create_info.format,
-        .extent = create_info.extent,
-        .mip_levels = create_info.mip_levels,
-        .array_layers = create_info.array_layers,
-        .samples = create_info.samples,
-        .tiling = create_info.tiling,
-        .usage = create_info.usage,
-        .sharing_mode = if (queue_family_indices.len > 1) .concurrent else .exclusive,
-        .queue_family_index_count = if (queue_family_indices.len > 1) @intCast(queue_family_indices.len) else 0,
-        .p_queue_family_indices = if (queue_family_indices.len > 1) queue_family_indices.ptr else null,
-        .initial_layout = create_info.initial_layout,
-    }, ctx.vk_allocator.capture());
-    return image;
 }
 
 pub fn createImageView(self: *Engine, create_info: ImageViewCreateInfo) !vk.ImageView {

src/engine/Materials.zig

@@ -1,4 +1,9 @@
-//! Module for loading persistent materials.
+//! Module for loading persistent materials, which are all stored in a single
+//! storage buffer in VRAM.
+//!
+//! This module is intended to be initialized once and to persist until the end
+//! of the whole program's runtime. Trying to use it in any other way will
+//! result in weird behavior.
 
 const Materials = @This();
 const std = @import("std");
@@ -13,11 +18,13 @@ const Engine = @import("../engine/Engine.zig");
 const Textures = @import("Textures.zig");
 
 pub const Id = enum(u16) {
-    // VOLATILE Synchronize explicit values with `init` implementation.
+    // VOLATILE When modifying the list of explicitly defined material IDs (i.e.
+    // any explicit enum value), we need to update `Materials.init`
+    // implementation.
 
     /// A material ID that can be used as a "null" material. An object with this
-    /// material ID must not be rendered. If this ID is rendered, an "error"
+    /// material ID must not be rendered. If this material is rendered anyway,
-    /// replacement material will be used.
+    /// an appropriate "error"-looking material will be used.
     empty,
     _,
 

src/engine/Swapchain.zig

@@ -218,6 +218,10 @@ pub fn acquire(self: *Swapchain) !void {
     self.image_index = res.image_index;
 }
 
+pub fn getCurrentSwapchainImage(self: *Swapchain) *const SwapchainImage {
+    return &self.swapchain_images[self.image_index.?];
+}
+
 pub const PresentInfo = struct {
     command_buffer: CommandBuffer,
     wait_semaphores: []const WaitSemaphore = &.{},
@@ -227,7 +231,7 @@ pub fn present(self: *Swapchain, present_info: PresentInfo) !void {
     const allocator_frame = ctx.allocator_frame;
     const engine = ctx.engine;
 
-    const current_swapchain_image = &self.swapchain_images[self.image_index.?];
+    const current_swapchain_image = self.getCurrentSwapchainImage();
 
     // --- SUBMIT COMMAND BUFFER -----------------------------------------------
 

src/engine/Texture.zig

@@ -5,6 +5,7 @@ const ctx = @import("../AppContext.zig");
 const vk = @import("vulkan");
 
 const CommandBuffer = @import("CommandBuffer.zig");
+const DeviceAllocation = @import("DeviceAllocation.zig");
 const Engine = @import("Engine.zig");
 const StagingBuffer = @import("StagingBuffer.zig");
 const TargetQueue = @import("TargetQueue.zig").TargetQueue;
@@ -68,11 +69,14 @@ pub const InitInfo = struct {
     height: u32,
     usage: Usage,
     target_queue: TargetQueue,
+    device_allocation: ?*DeviceAllocation = null,
     name: ?[]const u8 = null,
 };
 
 image: vk.Image,
 image_view: vk.ImageView,
+/// Is `.null_handle` when external device memory is provided via
+/// `device_allocation` in init info.
 device_memory: vk.DeviceMemory,
 target_queue: TargetQueue,
 
@@ -114,14 +118,20 @@ pub fn init(init_info: InitInfo) !Texture {
         engine.setObjectName(image, "I {s} [{s}]", .{ name, @tagName(init_info.usage) });
     }
 
-    const memory_requirements = engine.getImageMemoryRequirements(image);
+    var device_memory: vk.DeviceMemory = .null_handle;
-    const device_memory = try engine.allocate(memory_requirements, .{ .device_local_bit = true });
     errdefer engine.freeMemory(device_memory);
+
+    if (init_info.device_allocation) |device_allocation| {
+        try device_allocation.bindImage(image);
+    } else {
+        const memory_requirements = engine.getImageMemoryRequirements(image);
+        device_memory = try engine.allocate(memory_requirements, .{ .device_local_bit = true });
         if (init_info.name) |name| {
             engine.setObjectName(device_memory, "DM {s} [{s}]", .{ name, @tagName(init_info.usage) });
         }
 
         try engine.bindImageMemory(image, device_memory, 0);
+    }
 
     const image_view = try engine.createImageView(.{
         .image = image,

src/engine/Textures.zig

@@ -5,10 +5,12 @@ const std = @import("std");
 
 const ctx = @import("../AppContext.zig");
 const media = @import("media");
+const vk = @import("vulkan");
 
-const Atom = @import("../engine/Atom.zig").Atom;
+const Atom = @import("Atom.zig").Atom;
-const Engine = @import("../engine/Engine.zig");
+const DeviceAllocation = @import("DeviceAllocation.zig");
-const Texture = @import("../engine/Texture.zig");
+const Engine = @import("Engine.zig");
+const Texture = @import("Texture.zig");
 
 pub const Id = enum(u16) {
     // VOLATILE Synchronize explicit values with `init` implementation.
@@ -62,13 +64,15 @@ map: std.AutoHashMapUnmanaged(Key, Id),
 /// Stores all `Texture` structs and maps a texture ID to a `Texture` struct.
 /// Preallocated with `allocator_general`.
 array: std.ArrayList(Texture),
+device_allocation: DeviceAllocation,
 
-/// 4096 textures of usage `.base_color` and 16×16 dimensions should take 4 MiB
-/// in VRAM.
 pub const max_textures = 4096;
+/// Enough for 4096 textures of usage `.base_color` and 64×64 dimensions.
+pub const max_memory = 64 * 1024 * 1024;
 
 pub fn init() !Textures {
     const allocator_general = ctx.allocator_general;
+    const engine = ctx.engine;
 
     var map: std.AutoHashMapUnmanaged(Key, Id) = .empty;
     errdefer map.deinit(allocator_general);
@@ -82,6 +86,35 @@ pub fn init() !Textures {
         array.deinit(allocator_general);
     }
 
+    var device_allocation = try engine.allocateForImage(
+        .{
+            .image_type = .@"2d",
+            .format = .r8g8b8a8_unorm,
+            .extent = .{
+                .width = 1,
+                .height = 1,
+                .depth = 1,
+            },
+            .mip_levels = 1,
+            .array_layers = 1,
+            .samples = .{ .@"1_bit" = true },
+            .tiling = .optimal,
+            .usage = .{
+                .transfer_dst_bit = true,
+                .sampled_bit = true,
+            },
+            .queue_family_indices = &.{
+                engine.graphics_queue.allocation.family,
+                engine.transfer_queue.allocation.family,
+            },
+            .initial_layout = .undefined,
+        },
+        .{ .color_bit = true },
+        max_memory,
+        .{ .device_local_bit = true },
+    );
+    errdefer engine.freeMemory(device_allocation.device_memory);
+
     // VOLATILE Synchronize with explicit values on top of `Id` type.
 
     const empty_base_color_texture = try Texture.init(.{
@@ -89,6 +122,7 @@ pub fn init() !Textures {
         .height = 1,
         .usage = .base_color,
         .target_queue = .graphics,
+        .device_allocation = &device_allocation,
         .name = "@Empty",
     });
     array.appendAssumeCapacity(empty_base_color_texture);
@@ -98,6 +132,7 @@ pub fn init() !Textures {
         .height = 1,
         .usage = .emissive,
         .target_queue = .graphics,
+        .device_allocation = &device_allocation,
         .name = "@Empty",
     });
     array.appendAssumeCapacity(empty_emissive_texture);
@@ -107,6 +142,7 @@ pub fn init() !Textures {
         .height = 1,
         .usage = .normal,
         .target_queue = .graphics,
+        .device_allocation = &device_allocation,
         .name = "@Empty",
     });
     array.appendAssumeCapacity(empty_normal_texture);
@@ -116,6 +152,7 @@ pub fn init() !Textures {
         .height = 1,
         .usage = .occlusion_roughness_metallic,
         .target_queue = .graphics,
+        .device_allocation = &device_allocation,
         .name = "@Empty",
     });
     array.appendAssumeCapacity(empty_occlusuion_roughness_metallic_texture);
@@ -128,6 +165,7 @@ pub fn init() !Textures {
     return .{
         .map = map,
         .array = array,
+        .device_allocation = device_allocation,
     };
 }
 
@@ -139,6 +177,7 @@ pub fn deinit(self: *Textures) void {
     for (self.array.items) |*texture| {
         texture.deinit();
     }
+    self.device_allocation.deinit();
     self.array.deinit(allocator_general);
     self.map.deinit(allocator_general);
     self.* = undefined;
@@ -201,7 +240,7 @@ pub fn getOrLoad(
             const id = Id.fromIndexSafe(self.array.items.len) catch |err| switch (err) {
                 error.Overflow => return error.OutOfTextures,
             };
-            const texture = try loadTexture(stbi, filename, usage);
+            const texture = try loadTexture(stbi, filename, usage, &self.device_allocation);
 
             self.map.putAssumeCapacityNoClobber(key, id);
             self.array.appendAssumeCapacity(texture);
@@ -239,7 +278,7 @@ pub fn getOrLoadAtom(
             const id = Id.fromIndexSafe(self.array.items.len) catch |err| switch (err) {
                 error.Overflow => return error.OutOfTextures,
             };
-            const texture = try loadTexture(stbi, filename.toString(), usage);
+            const texture = try loadTexture(stbi, filename.toString(), usage, &self.device_allocation);
 
             self.map.putAssumeCapacityNoClobber(key, id);
             self.array.appendAssumeCapacity(texture);
@@ -255,6 +294,7 @@ fn loadTexture(
     stbi: *media.stbi,
     filename: []const u8,
     usage: Texture.Usage,
+    device_allocation: *DeviceAllocation,
 ) !Texture {
     const io = ctx.io;
 
@@ -292,6 +332,7 @@ fn loadTexture(
         .height = img.height,
         .usage = usage,
         .target_queue = .graphics,
+        .device_allocation = device_allocation,
         .name = filename,
     });
     errdefer texture.deinit();

src/shaders.zig

@@ -1,9 +1,9 @@
 const std = @import("std");
 const vm = @import("vecmath");
 
-const Materials = @import("assets/Materials.zig");
+const Materials = @import("engine/Materials.zig");
 const GenericBuffer = @import("engine/GenericBuffer.zig").GenericBuffer;
-const Textures = @import("assets/Textures.zig");
+const Textures = @import("engine/Textures.zig");
 
 pub const VertexBuffer = GenericBuffer(void, Vertex);
 pub const IndexBuffer = GenericBuffer(void, Index);

src/voxels.zig

@@ -3,7 +3,7 @@ const std = @import("std");
 const c = @import("const.zig");
 const vm = @import("vecmath");
 
-const Materials = @import("assets/Materials.zig");
+const Materials = @import("engine/Materials.zig");
 
 pub const Orientation = enum(u3) {
     negative_x = 0b111,