WIP: Switch to WebGPU-like API

1 files changed, 67 insertions, 59 deletions

diff --git a/chickadee.scm b/chickadee.scm
index 656ce0b..8343a6b 100644
--- a/chickadee.scm
+++ b/chickadee.scm
@@ -16,7 +16,7 @@
 
 ;;; Commentary:
 ;;
-;; Simple SDL + OpenGL game loop implementation.
+;; Core event loop.
 ;;
 ;;; Code:
 
@@ -26,12 +26,12 @@
   #:use-module (chickadee game-loop)
   #:use-module (chickadee math matrix)
   #:use-module (chickadee graphics color)
-  #:use-module (chickadee graphics engine)
   #:use-module (chickadee graphics gpu)
-  #:use-module (chickadee graphics viewport)
+  ;; #:use-module (chickadee graphics viewport)
   #:use-module (chickadee utils)
   #:use-module (ice-9 atomic)
   #:use-module (ice-9 match)
+  #:use-module (ice-9 threads)
   #:use-module (sdl2)
   #:use-module (sdl2 events)
   #:use-module ((sdl2 input game-controller) #:prefix sdl2:)
@@ -76,6 +76,9 @@
   #:re-export (abort-game
                current-timestep))
 
+
+
+
 (define %time-freq (exact->inexact internal-time-units-per-second))
 
 (define (elapsed-time)
@@ -155,10 +158,8 @@ not being pushed at all."
 
 (define* (make-window #:key (title "Chickadee") fullscreen? resizable?
                       (width 640) (height 480) (multisample? #t))
-  ;; Hint that we want OpenGL 3.2 Core profile.  Doesn't mean we'll
-  ;; get it, though!
-  (sdl2:set-gl-attribute! 'context-major-version 3)
-  (sdl2:set-gl-attribute! 'context-major-version 2)
+  ;; Hint that we want the core profile with deprecated features
+  ;; disabled.  Doesn't mean we'll get it, though!
   (sdl2:set-gl-attribute! 'context-profile-mask 1) ; core profile
   (sdl2:set-gl-attribute! 'stencil-size 8) ; 8-bit stencil buffer
   (if multisample?
@@ -254,7 +255,8 @@ border is disabled, otherwise it is enabled.")
                    (window-height 480)
                    window-fullscreen?
                    window-resizable?
-                   (clear-color %default-clear-color)
+                   (clear-color black;; %default-clear-color
+                                )
                    (update-hz 60)
                    (load noop)
                    (update noop)
@@ -304,20 +306,19 @@ border is disabled, otherwise it is enabled.")
                                   #:fullscreen? window-fullscreen?
                                   #:resizable? window-resizable?
                                   #:multisample? #f)))
-         (default-viewport (vector
-                            (make-viewport 0 0 window-width window-height
-                                           #:clear-color clear-color)))
+         ;; (default-viewport (vector
+         ;;                    (make-viewport 0 0 window-width window-height
+         ;;                                   #:clear-color clear-color)))
          (default-projection (vector
                               (orthographic-projection 0 window-width
                                                        window-height 0
                                                        0 1)))
-         (gpu (make-gpu (window-gl-context window)))
-         (gfx (make-graphics-engine gpu)))
+         (gpu (make-gpu (unwrap-window window) (window-gl-context window))))
     (define (invert-y y)
       ;; SDL's origin is the top-left, but our origin is the bottom
       ;; left so we need to invert Y coordinates that SDL gives us.
       (- window-height y))
-    (define (input-sdl)
+    (define (flush-sdl-input)
       (define (process-event event)
         (cond
          ((quit-event? event)
@@ -398,9 +399,9 @@ border is disabled, otherwise it is enabled.")
             ((width height)
              (set! window-width width)
              (set! window-height height)
-             (vector-set! default-viewport 0
-                          (make-viewport 0 0 width height
-                                         #:clear-color clear-color))
+             ;; (vector-set! default-viewport 0
+             ;;              (make-viewport 0 0 width height
+             ;;                             #:clear-color clear-color))
              (vector-set! default-projection 0
                           (orthographic-projection 0 width height 0 0 1))
              (window-resize width height))))))
@@ -409,51 +410,58 @@ border is disabled, otherwise it is enabled.")
         (when event
           (process-event event)
           (loop (poll-event)))))
-    (define (update-sdl dt)
-      (input-sdl)
-      (update dt)
-      ;; Update audio after updating game state so that any sounds
-      ;; that were queued to play this frame start playing immediately.
-      (update-audio)
-      ;; Free any GPU resources that have been GC'd.
-      (graphics-engine-gc gfx))
-    (define (render-sdl-opengl alpha)
-      (graphics-engine-reset! gfx)
-      ;; Enable seamless cube maps.
-      ;; TODO: This should go somewhere else.
-      (set-gpu-seamless-cube-maps! (current-gpu) #t)
-      (with-viewport (vector-ref default-viewport 0)
-        (clear-viewport)
-        (with-graphics-state ((projection (vector-ref default-projection 0)))
-          (draw alpha)))
-      (sdl2:swap-gl-window (unwrap-window window)))
     (define (on-error e stack)
       (error e stack)
       ;; Flush all input events that have occurred while in the error
       ;; state.
       (while (poll-event) #t))
-    (dynamic-wind
-      (const #t)
-      (lambda ()
-        (parameterize ((current-window window)
-                       (current-graphics-engine gfx))
-          ;; Attempt to activate vsync, if possible.  Some systems do
-          ;; not support setting the OpenGL swap interval.
-          (catch #t
-            (lambda ()
-              (sdl2:set-gl-swap-interval! 'vsync))
-            (lambda args
-              (display "warning: could not enable vsync\n"
-                       (current-error-port))))
-          (sdl2:load-game-controller-mappings!
-           (scope-datadir "gamecontrollerdb.txt"))
-          (run-game* #:init load
-                     #:update update-sdl
-                     #:render render-sdl-opengl
-                     #:error (and error on-error)
-                     #:time elapsed-time
-                     #:update-hz update-hz)))
+    ;; The game loop will run in its own thread so that updating game
+    ;; state can happen while rendering and input are being processed
+    ;; in the main thread and thus improving overall performance.
+    ;; This is where all user code is executed.
+    (define (game-loop)
+      (parameterize ((current-window window)
+                     (current-gpu gpu))
+        (run-game* #:init load
+                   #:update update
+                   #:render draw
+                   #:error (and error on-error)
+                   #:time elapsed-time
+                   #:update-hz update-hz)))
+    ;; The main loop handles the input and rendering queues, as input
+    ;; polling and GPU calls have to be done from the main thread in
+    ;; SDL.
+    (define (main-loop)
+      (flush-sdl-input)
+      (update-audio)
+      ;; (graphics-engine-reset! gfx)
+      ;; Enable seamless cube maps.
+      ;; TODO: This should go somewhere else.
+      ;; (set-gpu-seamless-cube-maps! (current-gpu) #t)
+      ;; (with-viewport (vector-ref default-viewport 0)
+      ;;   (clear-viewport)
+      ;;   (with-graphics-state ((projection (vector-ref default-projection 0)))
+      ;;     (draw alpha)))
+      (gpu-tick gpu)
+      (gpu-swap gpu)
+      ;; Free any GPU resources that have been GC'd.
+      (gpu-gc gpu)
+      (usleep 1) ; don't use 100% of the cpu pls
+      (main-loop))
+    ;; Attempt to activate vsync, if possible.  Some systems do
+    ;; not support setting the OpenGL swap interval.
+    (catch #t
       (lambda ()
-        (quit-audio)
-        (sdl2:delete-gl-context! (window-gl-context window))
-        (sdl2:close-window! (unwrap-window window))))))
+        (sdl2:set-gl-swap-interval! 'vsync))
+      (lambda args
+        (display "warning: could not enable vsync\n"
+                 (current-error-port))))
+    ;; Make lots of game controllers "just work."
+    (sdl2:load-game-controller-mappings!
+     (scope-datadir "gamecontrollerdb.txt"))
+    ;; Launch game loop in a separate thread and start the main loop.
+    (let ((game-thread (call-with-new-thread game-loop)))
+      (main-loop)
+      (quit-audio)
+      (sdl2:delete-gl-context! (window-gl-context window))
+      (sdl2:close-window! (unwrap-window window)))))