Iterative texture loading

src/assets.zig

@@ -47,6 +47,9 @@ const AssetContext = struct {
 
 pub const LoadError = error{
     DependencyError,
+    ParsingError,
+    SdlError,
+    FileTooBig,
 } || std.mem.Allocator.Error || std.fs.File.OpenError || std.fs.File.ReadError;
 
 pub const AssetType = enum {
@@ -129,8 +132,11 @@ pub fn AssetContainer(comptime T: type) type {
                     // TODO: Do something else while the asset is locked?
                     self.asset_pointer.mutex.lock();
                     defer self.asset_pointer.mutex.unlock();
-                    self.asset_pointer.load(Game.alloc);
                     self.last_state = self.asset_pointer.state;
+                    if (self.last_state == .not_loaded) {
+                        self.asset_pointer.load(Game.alloc);
+                        self.last_state = self.asset_pointer.state;
+                    }
                     if (self.last_state == .loaded) {
                         self.data_pointer = @alignCast(@ptrCast(self.asset_pointer.data));
                     }

src/assets/texture.zig

@@ -11,17 +11,88 @@ sampler: *sdl.GPUSampler,
 pub fn load(path: []const u8, alloc: std.mem.Allocator) Assets.LoadError!@This() {
     _ = alloc;
     var file = Assets.load(.file, path);
-    defer Assets.free(file);
+    const data = (file.getSync() catch return error.DependencyError).bytes;
-    const data = (try file.getSync()).bytes;
+
+    var width: u32 = undefined;
+    var height: u32 = undefined;
+    var channels: u32 = undefined;
+    const image = c.stbi_load_from_memory(
+        @ptrCast(data),
+        @intCast(data.len),
+        @ptrCast(&width),
+        @ptrCast(&height),
+        @ptrCast(&channels),
+        4,
+    );
+    Assets.free(file);
+    if (image == null) return error.ParsingError;
+    defer c.stbi_image_free(image);
+    const image_slice = image[0..@intCast(width * height * channels)];
+
+    if (width > 8192 or height > 8192) return error.FileTooBig;
+
+    const target_format = sdl.GPU_TEXTUREFORMAT_R8G8B8A8_UNORM;
+    const bytes_per_pixel = 4;
+
+    const texture = Graphics.createTexture(
+        width,
+        height,
+        target_format,
+        sdl.GPU_TEXTUREUSAGE_SAMPLER | sdl.GPU_TEXTUREUSAGE_COLOR_TARGET,
+        Graphics.MIP_LEVEL,
+    );
+    errdefer Graphics.freeTexture(texture);
+
+    const transfer_buffer_capacity = Graphics.TRANSFER_BUFFER_DEFAULT_CAPACITY;
+    const transfer_buffer = sdl.CreateGPUTransferBuffer(Graphics.device, &.{
+        .size = transfer_buffer_capacity,
+        .usage = sdl.GPU_TRANSFERBUFFERUSAGE_UPLOAD,
+    }) orelse return error.SdlError;
+    defer sdl.ReleaseGPUTransferBuffer(Graphics.device, transfer_buffer);
+
+    var rows_uploaded: u32 = 0;
+    while (rows_uploaded < height) {
+        const rows_to_upload = @min(height - rows_uploaded, transfer_buffer_capacity / width / bytes_per_pixel);
+        if (rows_to_upload == 0) return error.FileTooBig;
+
+        const command_buffer = sdl.AcquireGPUCommandBuffer(Graphics.device) orelse return error.SdlError;
+        {
+            errdefer _ = sdl.CancelGPUCommandBuffer(command_buffer);
+            const copy_pass = sdl.BeginGPUCopyPass(command_buffer) orelse return error.SdlError;
+            defer sdl.EndGPUCopyPass(copy_pass);
+
+            const map: [*]u8 = @ptrCast(sdl.MapGPUTransferBuffer(Graphics.device, transfer_buffer, false) orelse err.sdl());
+            @memcpy(map, image_slice[(rows_uploaded * width * bytes_per_pixel)..((rows_uploaded + rows_to_upload) * width * bytes_per_pixel)]);
+            sdl.UnmapGPUTransferBuffer(Graphics.device, transfer_buffer);
+
+            sdl.UploadToGPUTexture(copy_pass, &sdl.GPUTextureTransferInfo{
+                .offset = 0,
+                .pixels_per_row = width,
+                .rows_per_layer = rows_to_upload,
+                .transfer_buffer = transfer_buffer,
+            }, &sdl.GPUTextureRegion{
+                .texture = texture,
+                .mip_level = 0,
+                .layer = 0,
+                .x = 0,
+                .y = rows_uploaded,
+                .z = 0,
+                .w = width,
+                .h = rows_to_upload,
+                .d = 1,
+            }, false);
+        }
+        rows_uploaded += rows_to_upload;
+        if (rows_to_upload == height) {
+            sdl.GenerateMipmapsForGPUTexture(command_buffer, texture);
+        }
+        const fence = sdl.SubmitGPUCommandBufferAndAcquireFence(command_buffer) orelse return error.SdlError;
+        defer sdl.ReleaseGPUFence(Graphics.device, fence);
+        if (!sdl.WaitForGPUFences(Graphics.device, true, &fence, 1)) return error.SdlError;
+    }
+
+    const sampler = Graphics.createSampler();
 
-    var x: i32 = undefined;
-    var y: i32 = undefined;
-    var z: i32 = undefined;
-    const image = c.stbi_load_from_memory(@ptrCast(data), @intCast(data.len), &x, &y, &z, 4);
-    if (image == null) err.stbi();
-    const image_slice = image[0..@intCast(x * y * z)];
-    const texture, const sampler = Graphics.loadTexture(@intCast(x), @intCast(y), image_slice);
-    c.stbi_image_free(image);
     return .{
         .texture = texture,
         .sampler = sampler,
@@ -30,5 +101,6 @@ pub fn load(path: []const u8, alloc: std.mem.Allocator) Assets.LoadError!@This()
 
 pub fn unload(self: @This(), alloc: std.mem.Allocator) void {
     _ = alloc;
-    Graphics.unloadTexture(self.texture, self.sampler);
+    Graphics.freeTexture(self.texture);
+    Graphics.freeSampler(self.sampler);
 }

src/graphics.zig

@@ -12,8 +12,8 @@ pub const Mesh = struct {
     vertex_count: usize,
 };
 
-var window: *sdl.Window = undefined;
+pub var window: *sdl.Window = undefined;
-var device: *sdl.GPUDevice = undefined;
+pub var device: *sdl.GPUDevice = undefined;
 /// Only available while drawing
 var command_buffer: ?*sdl.GPUCommandBuffer = null;
 var render_pass: ?*sdl.GPURenderPass = null;
@@ -43,10 +43,10 @@ var to_resize: ?[2]u32 = null;
 
 const VERTEX_BUFFER_DEFAULT_CAPACITY = 1024;
 const VERTEX_BUFFER_GROWTH_MULTIPLIER = 2;
-const TRANSFER_BUFFER_DEFAULT_CAPACITY = 4096 * 1024;
 const BYTES_PER_VERTEX = 5 * 4;
 const DEPTH_FORMAT = sdl.GPU_TEXTUREFORMAT_D32_FLOAT;
-const MIP_LEVEL = 4;
+pub const TRANSFER_BUFFER_DEFAULT_CAPACITY = 256 * 1024;
+pub const MIP_LEVEL = 4;
 
 const Graphics = @This();
 pub fn create() void {
@@ -200,69 +200,6 @@ pub fn destroy() void {
     sdl.DestroyGPUDevice(Graphics.device);
 }
 
-pub fn loadTexture(width: u32, height: u32, texture_bytes: []const u8) struct { *sdl.GPUTexture, *sdl.GPUSampler } {
-    const target_format = sdl.GPU_TEXTUREFORMAT_R8G8B8A8_UNORM;
-
-    const texture = Graphics.createTexture(
-        width,
-        height,
-        target_format,
-        sdl.GPU_TEXTUREUSAGE_SAMPLER | sdl.GPU_TEXTUREUSAGE_COLOR_TARGET,
-        MIP_LEVEL,
-    );
-
-    const temp_command_buffer = sdl.AcquireGPUCommandBuffer(Graphics.device) orelse err.sdl();
-    {
-        const copy_pass = sdl.BeginGPUCopyPass(temp_command_buffer) orelse err.sdl();
-        defer sdl.EndGPUCopyPass(copy_pass);
-
-        const map: [*]u8 = @ptrCast(sdl.MapGPUTransferBuffer(Graphics.device, Graphics.transfer_buffer, true) orelse err.sdl());
-        @memcpy(map, texture_bytes);
-        sdl.UnmapGPUTransferBuffer(Graphics.device, Graphics.transfer_buffer);
-
-        sdl.UploadToGPUTexture(copy_pass, &sdl.GPUTextureTransferInfo{
-            .offset = 0,
-            .pixels_per_row = width,
-            .rows_per_layer = height,
-            .transfer_buffer = Graphics.transfer_buffer,
-        }, &sdl.GPUTextureRegion{
-            .texture = texture,
-            .mip_level = 0,
-            .layer = 0,
-            .x = 0,
-            .y = 0,
-            .z = 0,
-            .w = width,
-            .h = height,
-            .d = 1,
-        }, false);
-    }
-    sdl.GenerateMipmapsForGPUTexture(temp_command_buffer, texture);
-    if (!sdl.SubmitGPUCommandBuffer(temp_command_buffer)) err.sdl();
-
-    const sampler = sdl.CreateGPUSampler(Graphics.device, &sdl.GPUSamplerCreateInfo{
-        .address_mode_u = sdl.GPU_SAMPLERADDRESSMODE_CLAMP_TO_EDGE,
-        .address_mode_v = sdl.GPU_SAMPLERADDRESSMODE_CLAMP_TO_EDGE,
-        .address_mode_w = sdl.GPU_SAMPLERADDRESSMODE_CLAMP_TO_EDGE,
-        .mag_filter = sdl.GPU_FILTER_NEAREST,
-        .min_filter = sdl.GPU_FILTER_LINEAR,
-        .mipmap_mode = sdl.GPU_SAMPLERMIPMAPMODE_LINEAR,
-        .min_lod = 0,
-        .max_lod = 16,
-        .mip_lod_bias = -2,
-    }) orelse err.sdl();
-
-    return .{
-        texture,
-        sampler,
-    };
-}
-
-pub fn unloadTexture(texture: *sdl.GPUTexture, sampler: *sdl.GPUSampler) void {
-    sdl.ReleaseGPUSampler(Graphics.device, sampler);
-    sdl.ReleaseGPUTexture(Graphics.device, texture);
-}
-
 pub fn loadMesh(mesh_bytes: []const u8) Mesh {
     std.debug.assert(mesh_bytes.len < Graphics.transfer_buffer_capacity);
 
@@ -471,7 +408,7 @@ fn loadShader(path: []const u8, info: sdl.GPUShaderCreateInfo) *sdl.GPUShader {
     return sdl.CreateGPUShader(device, &updated_info) orelse err.sdl();
 }
 
-fn createTexture(width: u32, height: u32, format: c_uint, usage: c_uint, mip_level: u32) *sdl.GPUTexture {
+pub fn createTexture(width: u32, height: u32, format: c_uint, usage: c_uint, mip_level: u32) *sdl.GPUTexture {
     return sdl.CreateGPUTexture(device, &.{
         .format = format,
         .layer_count_or_depth = 1,
@@ -483,6 +420,28 @@ fn createTexture(width: u32, height: u32, format: c_uint, usage: c_uint, mip_lev
     }) orelse err.sdl();
 }
 
+pub fn freeTexture(texture: *sdl.GPUTexture) void {
+    sdl.ReleaseGPUTexture(Graphics.device, texture);
+}
+
+pub fn createSampler() *sdl.GPUSampler {
+    return sdl.CreateGPUSampler(Graphics.device, &sdl.GPUSamplerCreateInfo{
+        .address_mode_u = sdl.GPU_SAMPLERADDRESSMODE_CLAMP_TO_EDGE,
+        .address_mode_v = sdl.GPU_SAMPLERADDRESSMODE_CLAMP_TO_EDGE,
+        .address_mode_w = sdl.GPU_SAMPLERADDRESSMODE_CLAMP_TO_EDGE,
+        .mag_filter = sdl.GPU_FILTER_NEAREST,
+        .min_filter = sdl.GPU_FILTER_LINEAR,
+        .mipmap_mode = sdl.GPU_SAMPLERMIPMAPMODE_LINEAR,
+        .min_lod = 0,
+        .max_lod = 16,
+        .mip_lod_bias = -2,
+    }) orelse err.sdl();
+}
+
+pub fn freeSampler(sampler: *sdl.GPUSampler) void {
+    sdl.ReleaseGPUSampler(Graphics.device, sampler);
+}
+
 fn resetTextures(width: u32, height: u32) void {
     sdl.ReleaseGPUTexture(Graphics.device, Graphics.depth_texture);
     Graphics.depth_texture = createTexture(