render to texture

.gitignore

@@ -1,4 +1,7 @@
 
+# cloned wiki repo
+/doc/wiki
+
 # KDE :')
 .directory
 

wh-engine/main.lisp

@@ -77,31 +77,26 @@
     (setq *id-counter* (+ id 1)))
   id)
 
-(defvar *running-scenes* nil
+(defvar *world-scenes* ()
-  "List of running scenes.")
+  "List of all running scenes.")
 
 (defun add-scene (scene)
   "Add a scene to the list of running scenes."
   (declare (type scene scene))
 
-  (push scene *running-scenes*)
+  (push scene *world-scenes*)
   scene)
 
 (defun remove-scene (scene)
   "Remove a scene from the list of running scenes."
   (declare (type scene scene))
 
-  (setf *running-scenes* (remove scene *running-scenes*))
+  (setf *world-scenes* (remove scene *world-scenes*))
   scene)
 
 (defun get-scene (scene-id)
   "Get a scene by its ID."
-  (find-if (lambda (scene) (eq [scene id] scene-id)) *running-scenes*))
+  (find-if (lambda (scene) (eq [scene id] scene-id)) *world-scenes*))
-
-(defun update-all-scenes ()
-  "Update all running scenes."
-  (loop for scene in *running-scenes*
-        do [scene (update)]))
 
 (defvar *view-width* 384
   "View-space width in pixels.")
@@ -184,12 +179,41 @@
             sdl2-ffi:+sdl-patchlevel+)
     (finish-output)
     (sdl2:with-window (win :flags '(:shown :opengl)
-                           :w *view-width* :h *view-height*
+                           :w (* *view-width* *pixel-scale*) :h (* *view-height* *pixel-scale*)
-                           :title (format nil "wh-engine ~D.~D.~D (Affero GPL; NON-FREE USAGE PROHIBITED)"
+                           :title (format nil "wh-engine ~1{~D.~D.~D~} (Affero GPL; NON-FREE USAGE PROHIBITED)"
-                                          (nth 0 +version+) (nth 1 +version+) (nth 2 +version+)))
+                                          +version+))
       (sdl2:with-gl-context (gl-context win)
         (sdl2:gl-make-current win gl-context)
-        (gl:viewport 0 0 *view-width* *view-height*)
+        (let ((framebuf (car (gl:gen-framebuffers 1)))
+              (renderbuf (car (gl:gen-renderbuffers 1)))
+              (render-texture (car (gl:gen-textures 1)))
+              (win-width (nth-value 0 (sdl2:get-window-size win)))
+              (win-height (nth-value 1 (sdl2:get-window-size win))))
+          ;; set up framebuffer
+          (gl:bind-framebuffer :framebuffer framebuf)
+
+          (gl:bind-texture :texture-2d render-texture)
+          (gl:tex-image-2d :texture-2d 0 :rgba *view-width* *view-height* 0 :rgba :unsigned-byte (cffi:null-pointer))
+          (gl:tex-parameter :texture-2d :texture-wrap-s :clamp-to-edge)
+          (gl:tex-parameter :texture-2d :texture-wrap-t :clamp-to-edge)
+          (gl:tex-parameter :texture-2d :texture-min-filter :nearest)
+          (gl:tex-parameter :texture-2d :texture-mag-filter :nearest)
+          (gl:bind-texture :texture-2d 0)
+
+          (gl:framebuffer-texture-2d :framebuffer :color-attachment0 :texture-2d render-texture 0)
+
+          (gl:bind-renderbuffer :renderbuffer renderbuf)
+          (gl:renderbuffer-storage :renderbuffer :depth24-stencil8 *view-width* *view-height*)
+          (gl:bind-renderbuffer :renderbuffer 0)
+
+          (gl:framebuffer-renderbuffer :framebuffer :depth-stencil-attachment :renderbuffer renderbuf)
+
+          ;; make sure it's valid
+          (let ((result (gl:check-framebuffer-status :framebuffer)))
+            (unless (gl::enum= result :framebuffer-complete)
+              (error "Failed to create framebuffer: ~S" result)))
+
+          ;; set up gl
           (gl:matrix-mode :projection)
           (gl:ortho 0 *view-width*
                     0 *view-height*
@@ -199,13 +223,18 @@
           (gl:clear-color 0.0 0.0 0.0 1.0)
           (gl:clear :color-buffer)
           (gl:clear :depth-buffer)
-        (gl:enable :depth-test)
 
           (sdl2:with-event-loop (:method :poll)
             (:quit () t)
             (:idle ()
-                 (update-all-scenes)
+                   ;; update
+                   (loop for scene in *world-scenes*
+                         do [scene (update)])
+                   ;; draw to render texture
+                   (gl:bind-framebuffer :framebuffer framebuf)
+                   (gl:viewport 0 0 *view-width* *view-height*)
                    (gl:clear :color-buffer)
+                   (gl:enable :depth-test)
                    (let ((render-pass nil))
                      (loop for view-ptr in *world-views*
                            for view = (ensure-live (weak-pointer-value view-ptr))
@@ -213,9 +242,32 @@
                              do (progn
                                   (unless (eq [view render-pass] render-pass)
                                     (setf render-pass [view render-pass])
-                                  (gl:clear :depth-buffer)
+                                    (gl:clear :depth-buffer))
-                                  )
                                   [view (render-view *world-drawables*)])))
+
+                   ;; now draw to window
+                   (gl:bind-framebuffer :framebuffer 0)
+                   (gl:viewport 0 0 win-width win-height)
+                   (gl:clear :color-buffer)
+                   (gl:disable :depth-test)
+                   (gl:enable :texture-2d)
+                   (gl:bind-texture :texture-2d render-texture)
+                   (gl:matrix-mode :modelview)
+                   (gl:load-identity)
+
+                   (gl:with-primitive :quads
+                     (gl:color 1.0 1.0 1.0 1.0)
+                     (gl:tex-coord 0.0 0.0)
+                     (gl:vertex 0.0 0.0)
+                     (gl:tex-coord 1.0 0.0)
+                     (gl:vertex *view-width* 0.0)
+                     (gl:tex-coord 1.0 1.0)
+                     (gl:vertex *view-width* *view-height*)
+                     (gl:tex-coord 0.0 1.0)
+                     (gl:vertex 0.0 *view-height*))
+
+                   (gl:disable :texture-2d)
+
                    (gl:flush)
                    (sdl2:gl-swap-window win)))
-        ))))
+          )))))

wh-engine/render/drawable.lisp

@@ -33,10 +33,9 @@
   (cons (vec2 -0.5 -0.5) (vec2 0.5 0.5)))
 
 (defmethod draw ((this drawable-test) view)
-  (gl:begin :quads)
   (gl:color (vx4 [this colour]) (vy4 [this colour]) (vz4 [this colour]) (vw4 [this colour]))
+  (gl:with-primitives :quads
     (gl:vertex -0.5 -0.5  0.0 1.0)
     (gl:vertex  0.5 -0.5  0.0 1.0)
     (gl:vertex  0.5  0.5  0.0 1.0)
-  (gl:vertex -0.5  0.5  0.0 1.0)
+    (gl:vertex -0.5  0.5  0.0 1.0)))
-  (gl:end))