adding command descriptors and buffer base

src/vulkan/Buffer.zig

@@ -2,12 +2,42 @@ const std = @import("std");
 const vk = @import("vulkan");
 
 const VkError = @import("error_set.zig").VkError;
+const DeviceMemory = @import("DeviceMemory.zig");
 const Device = @import("Device.zig");
 
 const Self = @This();
 pub const ObjectType: vk.ObjectType = .buffer;
 
-owner: *const Device,
+owner: *Device,
 size: vk.DeviceSize,
 offset: vk.DeviceSize,
 usage: vk.BufferUsageFlags,
+memory: ?*DeviceMemory,
+allowed_memory_types: u32,
+
+vtable: *const VTable,
+
+pub const VTable = struct {
+    getMemoryRequirements: *const fn (*Self, *vk.MemoryRequirements) void,
+};
+
+pub fn init(device: *Device, allocator: std.mem.Allocator, info: *const vk.BufferCreateInfo) VkError!Self {
+    _ = allocator;
+    return .{
+        .owner = device,
+        .size = info.size,
+        .offset = 0,
+        .usage = info.usage,
+        .memory = null,
+        .allowed_memory_types = 0,
+        .vtable = undefined,
+    };
+}
+
+pub inline fn bindMemory(self: *Self, memory: *DeviceMemory, offset: vk.DeviceSize) VkError!void {
+    if (offset >= self.size or self.allowed_memory_types & memory.memory_type_index == 0) {
+        return VkError.ValidationFailed;
+    }
+    self.memory = memory;
+    self.offset = offset;
+}