Implemented rotations

assets/shaders/shader.vert

@@ -15,6 +15,7 @@ layout (binding = 1) uniform ViewUniform {
 layout (binding = 4) uniform TransformUniform {
     mat4 translation;
     mat4 scale;
+    mat4 rotation;
 } transform;
 
 layout(location = 2) out vec3 Normal;
@@ -22,7 +23,7 @@ layout(location = 3) out vec3 FragPos;
 layout(location = 4) out vec2 TexCoords;
 
 void main() {
-    mat4 transformation = transform.translation * transform.scale;
+    mat4 transformation = transform.translation * transform.scale * transform.rotation;
     vec4 out_vec = proj.proj * view.view * transformation * vec4(vertPos, 1.0);
     FragPos = vec3(vec4(vertPos, 1.0));
     Normal = normal;

src/ecs/entities.zig

@@ -26,7 +26,7 @@ pub const Human = struct {
 // TODO(ernesto): Move pool to its own file
 pub const Pool = struct {
     humans: std.MultiArrayList(Human),
-    resources: Resources,
+    resources: *Resources,
     allocator: Allocator,
     system_groups: std.ArrayList(SystemGroup),
     sync_groups: std.ArrayList(SyncGroup),
@@ -34,7 +34,7 @@ pub const Pool = struct {
     wait_group: std.Thread.WaitGroup,
     mutex: std.Thread.Mutex,
 
-    pub fn init(allocator: Allocator, resources: Resources) !@This() {
+    pub fn init(allocator: Allocator, resources: *Resources) !@This() {
         var pool = @This(){
             .humans = .{},
             .resources = resources,

src/math.zig

@@ -11,18 +11,21 @@ pub const Axis = struct {
     pub const z: [3]f32 = .{0.0, 0.0, 1.0};
 };
 
-pub const Transform = struct {
+pub const Transform = extern struct {
     translation: Matrix,
     scale: Matrix,
+    rotation_matrix: Matrix,
     rotation: Quaternion,
 
     pub fn init(position: [3]f32, scale: [3]f32, rotation: [3]f32) Transform {
         var translation = Matrix.identity();
         translation.translate(position);
+        const quaternion = Quaternion.fromEulerAngles(rotation);
 
         return .{
             .translation = translation,
-            .rotation = Quaternion.fromEulerAngles(rotation),
+            .rotation = quaternion,
+            .rotation_matrix = quaternion.matrix(),
             .scale = Matrix.scale(scale),
         };
     }
@@ -35,10 +38,11 @@ pub const Transform = struct {
         const delta = Quaternion.fromAxisAngle(axis, angle);
         self.rotation = self.rotation.mul(delta);
         self.rotation = self.rotation.normalize();
+        self.rotation_matrix = self.rotation.matrix();
     }
 };
 
-pub const Matrix = struct {
+pub const Matrix = extern struct {
     rows: [4][4]f32,
 
     pub fn lookAt(eye: [3]f32, target: [3]f32, arbitrary_up: [3]f32) Matrix {
@@ -134,7 +138,7 @@ pub const Matrix = struct {
     }
 };
 
-const Quaternion = struct {
+pub const Quaternion = extern struct {
     w: f32,
     x: f32,
     y: f32,
@@ -150,7 +154,7 @@ const Quaternion = struct {
             .w = cos(half_angle),
             .x = axis[0] * s,
             .y = axis[1] * s,
-            .z = axis[3] * s,
+            .z = axis[2] * s,
         };
     }
 

src/renderer/Renderer.zig

@@ -20,6 +20,7 @@ current_frame: u32,
 vertex_buffer: vk.Buffer,
 index_buffer: vk.Buffer,
 transform: math.Transform,
+previous_time: std.time.Instant,
 
 pub fn init(allocator: Allocator, instance_handle: vk.c.VkInstance, surface_handle: vk.c.VkSurfaceKHR) !Renderer {
     const instance: vk.Instance = .{ .handle = instance_handle };
@@ -68,7 +69,8 @@ pub fn init(allocator: Allocator, instance_handle: vk.c.VkInstance, surface_hand
         // TODO: Why are we storing the buffer and not the Mesh?
         .vertex_buffer = triangle.vertex_buffer,
         .index_buffer = triangle.index_buffer,
-        .transform = math.Transform.init(.{0.0, 0.0, 0.0}, .{1.0, 1.0, 1.0}, .{0.0, 0.0, 0.0}),
+        .transform = math.Transform.init(.{0.0, 0.0, 0.0}, .{1.0, 1.0, 1.0}, .{0.0, math.rad(45.0), 0.0}),
+        .previous_time = try std.time.Instant.now(),
     };
 }
 
@@ -87,6 +89,10 @@ pub fn render(pool: *ecs.Pool) anyerror!void {
     var renderer = pool.resources.renderer;
     var camera = pool.resources.camera;
 
+    const now = try std.time.Instant.now();
+    const delta_time: f32 = @as(f32, @floatFromInt(now.since(renderer.previous_time))) / @as(f32, 1_000_000_000.0);
+    renderer.previous_time = now;
+
     const view_memory = renderer.graphics_pipeline.view_memory;
     @memcpy(view_memory[0..@sizeOf(math.Matrix)], std.mem.asBytes(&camera.getView()));
 
@@ -96,8 +102,10 @@ pub fn render(pool: *ecs.Pool) anyerror!void {
     view_pos[1] = camera.position[1];
     view_pos[2] = camera.position[2];
 
+    renderer.transform.rotate(math.rad(10) * delta_time, .{0.0, 1.0, 0.0});
+
     const transform_memory = renderer.graphics_pipeline.transform_memory;
-    @memcpy(transform_memory[0..@sizeOf(math.Transform)], std.mem.asBytes(&renderer.transform));
+    @memcpy(transform_memory[0..(@sizeOf(math.Transform)-@sizeOf(math.Quaternion))], std.mem.asBytes(&renderer.transform)[0..(@sizeOf(math.Transform)-@sizeOf(math.Quaternion))]);
 
     try renderer.device.waitFence(renderer.current_frame);
     const image = try renderer.swapchain.nextImage(renderer.device, renderer.current_frame);

src/renderer/vulkan.zig

@@ -548,7 +548,7 @@ pub fn GraphicsPipeline(comptime n: usize) type {
 
             c.vkUpdateDescriptorSets(device.handle, 1, &write_view_descriptor_set, 0, null);
 
-            const transform_buffer = try device.createBuffer(BufferUsage{ .uniform_buffer = true, .transfer_dst = true }, BufferFlags{ .device_local = true }, @sizeOf(math.Transform));
+            const transform_buffer = try device.createBuffer(BufferUsage{ .uniform_buffer = true, .transfer_dst = true }, BufferFlags{ .device_local = true }, @sizeOf(math.Transform) - @sizeOf(math.Quaternion));
 
             var transform_data: [*c]u8 = undefined;
 

src/sideros.zig

@@ -12,6 +12,7 @@ var gpa = std.heap.GeneralPurposeAllocator(.{}){};
 const allocator = gpa.allocator();
 var pool: ecs.Pool = undefined;
 var renderer: Renderer = undefined;
+var resources: ecs.Resources = undefined;
 
 fn init_mods() void {
     var global_runtime = mods.GlobalRuntime.init(allocator);
@@ -43,14 +44,16 @@ fn init_mods() void {
 }
 
 export fn sideros_init(init: api.GameInit) callconv(.c) void {
-    pool = ecs.Pool.init(allocator, .{
+    resources = .{
         .camera = .{
             .position = .{ 5.0, 5.0, 5.0 },
             .target = .{ 0.0, 0.0, 0.0 },
         },
         .renderer = undefined,
         .input = .{ .key_pressed = .{false} ** @intFromEnum(ecs.Input.KeyCode.menu) },
-    }) catch @panic("TODO: Gracefully handle error");
+    };
+
+    pool = ecs.Pool.init(allocator, &resources) catch @panic("TODO: Gracefully handle error");
     // TODO(ernesto): I think this @ptrCast are unavoidable but maybe not?
     renderer = Renderer.init(allocator, @ptrCast(init.instance), @ptrCast(init.surface)) catch @panic("TODO: Gracefully handle error");
     pool.addSystemGroup(&[_]ecs.System{Renderer.render}, true) catch @panic("TODO: Gracefuly handle error");