Working example

main.odin

@@ -0,0 +1,44 @@
+package main
+
+import "core:fmt"
+import "core:math"
+import sdl "sdl3"
+
+main :: proc() {
+	fmt.println("Hello world")
+	_ = sdl.Init(sdl.INIT_VIDEO)
+
+	window: ^sdl.Window
+	renderer: ^sdl.Renderer
+	sdl.CreateWindowAndRenderer("SDL3 with Odin", 800, 600, {.RESIZABLE}, &window, &renderer)
+	sdl.SetRenderVSync(renderer, 1)
+
+	running := true
+	for running {
+		e: sdl.Event
+		for sdl.PollEvent(&e) {
+			#partial switch e.type {
+			case .QUIT:
+				running = false
+			}
+		}
+
+		now := f64(sdl.GetTicks()) / 1000.0 /* convert from milliseconds to seconds. */
+		/* choose the color for the frame we will draw. The sine wave trick makes it fade between colors smoothly. */
+		red :=   f32(0.5 + 0.5 * math.sin(now))
+		green := f32(0.5 + 0.5 * math.sin(now + math.PI * 2 / 3))
+		blue :=  f32(0.5 + 0.5 * math.sin(now + math.PI * 4 / 3))
+		sdl.SetRenderDrawColorFloat(
+			renderer,
+			red,
+			green,
+			blue,
+			sdl.ALPHA_OPAQUE_FLOAT,
+		) /* new color, full alpha. */
+
+		// sdl.SetRenderDrawColor(renderer, 255, 0, 0, 255)
+
+		sdl.RenderClear(renderer)
+		sdl.RenderPresent(renderer)
+	}
+}