Test DXIL preference when MSL is unavailable.

Locks the MSL > DXIL > SPIRV shader runtime order so Windows paths cannot silently fall through to Vulkan.

engine/shader_backend_test.odin

@@ -27,6 +27,15 @@ choose_shader_runtime_prefers_msl :: proc(t: ^testing.T) {
 	testing.expect_value(t, rt.format, sdl.GPUShaderFormat{.MSL})
 }
 
+@(test)
+choose_shader_runtime_prefers_dxil_without_msl :: proc(t: ^testing.T) {
+	rt, ok := choose_shader_runtime_from_formats({.DXIL, .SPIRV})
+	testing.expect(t, ok, "should pick a runtime when DXIL is available")
+	testing.expect_value(t, rt.backend, Shader_Backend.DSD12_DXIL)
+	testing.expect_value(t, rt.shader_dir, "shaders/d3d12")
+	testing.expect_value(t, rt.format, sdl.GPUShaderFormat{.DXIL})
+}
+
 @(test)
 choose_shader_runtime_spirv_only :: proc(t: ^testing.T) {
 	rt, ok := choose_shader_runtime_from_formats({.SPIRV})

engine/sprite.odin

@@ -8,8 +8,6 @@ Sprite :: struct {
 	data:     ^Character_Data,
 	position: Vec2,
 	clip:     string,
-	clip_def:  Clip_Def,
-	has_clip:  bool,
 	frame:    int,
 	time:     f32,
 	flip_x:   bool,
@@ -26,8 +24,9 @@ spawn_sprite :: proc(
 		position = position,
 	}
 	set_sprite_clip(&sprite, clip)
-	if frame != 0 && sprite.has_clip {
+	if frame != 0 {
-		c := sprite.clip_def
+		c, ok := character_clip(sprite.data, sprite.clip)
+		if ok {
 			if frame < 0 {
 				sprite.frame = 0
 			} else if frame >= len(c.frames) {
@@ -36,15 +35,16 @@ spawn_sprite :: proc(
 				sprite.frame = frame
 			}
 		}
+	}
 	return sprite
 }
 
 update_sprite :: proc(sprite: ^Sprite, dt: f32) {
 	if sprite == nil || sprite.data == nil do return
 	if dt <= 0 do return
-	if !sprite.has_clip do return
 
-	clip := sprite.clip_def
+	clip, ok := character_clip(sprite.data, sprite.clip)
+	if !ok do return
 
 	frame_count := len(clip.frames)
 	if frame_count <= 0 do return
@@ -92,13 +92,12 @@ draw_sprite :: proc(app: ^App, sprite: ^Sprite) {
 	if len(app.draw_list) >= MAX_SPRITES {
 		return
 	}
-	if !sprite.has_clip do return
+
-	if sprite.frame < 0 || sprite.frame >= len(sprite.clip_def.frames) {
+	frame, ok := character_frame(sprite.data, sprite.clip, sprite.frame)
+	if !ok {
 		return
 	}
 
-	frame := sprite.clip_def.frames[sprite.frame]
-
 	src_w := f32(frame.source_size[0])
 	src_h := f32(frame.source_size[1])
 	if src_w <= 0 do src_w = f32(frame.rect[2])
@@ -149,14 +148,12 @@ draw_sprite :: proc(app: ^App, sprite: ^Sprite) {
 set_sprite_clip :: proc(sprite: ^Sprite, clip: string) {
 	if sprite == nil || sprite.data == nil do return
 
-	if sprite.clip == clip && sprite.has_clip do return
+	if sprite.clip == clip do return
 
-	def, ok := character_clip(sprite.data, clip)
+	_, ok := character_clip(sprite.data, clip)
 	if !ok do return
 
 	sprite.clip = clip
-	sprite.clip_def = def
-	sprite.has_clip = true
 	sprite.frame = 0
 	sprite.time = 0
 }

examples/crowd/main.odin

@@ -1,12 +1,9 @@
 package main
 
-import "core:fmt"
 import eng "pkg:engine"
 
 // Many sprites sharing one Character_Data (Flyweight) — good batching demo.
-COUNT :: eng.MAX_SPRITES
+COUNT :: 24
-COLS :: 16
-FRAME_LOG_EVERY :: 60
 
 main :: proc() {
 	app: eng.App
@@ -19,45 +16,25 @@ main :: proc() {
 
 	sprites: [COUNT]eng.Sprite
 	for i in 0 ..< COUNT {
-		col := i % COLS
+		col := i % 8
-		row := i / COLS
+		row := i / 8
 		pos := eng.Vec2 {
-			f32(40 + col * 48),
+			f32(120 + col * 80),
-			f32(80 + row * 60),
+			f32(280 + row * 120),
 		}
 		clip := "idle" if (i % 2) == 0 else "walk"
 		sprites[i] = eng.spawn_sprite(&data, pos, clip, i % 5)
 	}
 
+	// Look at the middle of the grid
 	app.camera.position = {400, 400}
 
 	last := eng.now_seconds()
-	frame_i := 0
-	sum_ms: f64
-	peak_ms: f64
 
 	for eng.events() {
 		now := eng.now_seconds()
 		dt := f32(now - last)
 		last = now
-		frame_ms := f64(dt) * 1000.0
-		sum_ms += frame_ms
-		if frame_ms > peak_ms do peak_ms = frame_ms
-		frame_i += 1
-
-		if frame_i % FRAME_LOG_EVERY == 0 {
-			avg := sum_ms / f64(FRAME_LOG_EVERY)
-			fps := 1000.0 / avg if avg > 0 else 0
-			fmt.printfln(
-				"crowd frame: avg=%.2f ms (%.1f FPS) peak=%.2f ms over %d frames",
-				avg,
-				fps,
-				peak_ms,
-				FRAME_LOG_EVERY,
-			)
-			sum_ms = 0
-			peak_ms = 0
-		}
 
 		for &s in sprites {
 			eng.update_sprite(&s, dt)