graphics: Refactor model/phong/pbr modules to use new mesh module.

5 files changed, 206 insertions, 346 deletions

diff --git a/chickadee/graphics/model.scm b/chickadee/graphics/model.scm
index 9afa91c..77d67b8 100644
--- a/chickadee/graphics/model.scm
+++ b/chickadee/graphics/model.scm
@@ -29,13 +29,16 @@
   #:use-module (chickadee math quaternion)
   #:use-module (chickadee math vector)
   #:use-module (chickadee graphics buffer)
+  #:use-module (chickadee graphics blend)
   #:use-module (chickadee graphics color)
   #:use-module (chickadee graphics depth)
   #:use-module (chickadee graphics engine)
   #:use-module (chickadee graphics light)
+  #:use-module (chickadee graphics mesh)
   #:use-module (chickadee graphics multisample)
   #:use-module (chickadee graphics pbr)
   #:use-module (chickadee graphics phong)
+  #:use-module (chickadee graphics polygon)
   #:use-module (chickadee graphics shader)
   #:use-module (chickadee graphics texture)
   #:use-module (chickadee utils)
@@ -67,37 +70,18 @@
 ;;;
 
 (define-record-type <render-state>
-  (%make-render-state renderer view-matrix model-matrix world-model-matrix
-                      camera-position lights ambient-light-color)
+  (%make-render-state model-matrix world-model-matrix)
   render-state?
-  (renderer render-state-renderer)
-  (view-matrix render-state-view-matrix)
   (model-matrix render-state-model-matrix)
-  (world-model-matrix render-state-world-model-matrix)
-  (camera-position render-state-camera-position)
-  (lights render-state-lights)
-  (ambient-light-color render-state-ambient-light-color
-                       set-render-state-ambient-light-color!))
+  (world-model-matrix render-state-world-model-matrix))
 
-(define %default-ambient-light-color (make-color 0.03 0.03 0.03 1.0))
-
-(define (make-render-state renderer)
-  (%make-render-state renderer
-                      (make-identity-matrix4)
-                      (make-identity-matrix4)
-                      (make-identity-matrix4)
-                      (vec3 0.0 0.0 0.0)
-                      (make-vector %max-lights %disabled-light)
-                      %default-ambient-light-color))
+(define (make-render-state)
+  (%make-render-state (make-identity-matrix4)
+                      (make-identity-matrix4)))
 
 (define (render-state-reset! state)
-  (matrix4-identity! (render-state-view-matrix state))
   (matrix4-identity! (render-state-model-matrix state)))
 
-(define (render-state-view-matrix-mult! state matrix)
-  (let ((view (render-state-view-matrix state)))
-    (matrix4-mult! view view matrix)))
-
 (define (render-state-model-matrix-mult! state matrix)
   (let ((model (render-state-model-matrix state)))
     (matrix4-mult! model model matrix)))
@@ -107,70 +91,6 @@
                  matrix
                  (render-state-model-matrix state)))
 
-(define (set-render-state-camera-position! state position)
-  (vec3-copy! position (render-state-camera-position state)))
-
-(define (set-render-state-lights! state lights)
-  (let ((lv (render-state-lights state)))
-    (let loop ((i 0)
-               (lights lights))
-      (when (< i %max-lights)
-        (match lights
-          (()
-           (vector-set! lv i %disabled-light)
-           (loop (+ i 1) '()))
-          ((light . rest)
-           (vector-set! lv i light)
-           (loop (+ i 1) rest)))))))
-
-
-;;;
-;;; Primitive
-;;;
-
-;; A piece of a mesh.  Represents a single draw call.
-(define-record-type <primitive>
-  (make-primitive name vertex-array material)
-  primitive?
-  (name primitive-name)
-  (vertex-array primitive-vertex-array)
-  (material primitive-material))
-
-(define (draw-primitive/phong primitive state)
-  (shader-apply/phong (primitive-vertex-array primitive)
-                      (primitive-material primitive)
-                      (render-state-world-model-matrix state)
-                      (render-state-view-matrix state)
-                      (render-state-camera-position state)
-                      (render-state-lights state)
-                      (render-state-ambient-light-color state)))
-
-(define (draw-primitive/pbr primitive state)
-  (shader-apply/pbr (primitive-vertex-array primitive)
-                    (primitive-material primitive)
-                    (render-state-world-model-matrix state)
-                    (render-state-view-matrix state)
-                    (render-state-camera-position state)
-                    (render-state-lights state)
-                    (render-state-ambient-light-color state)))
-
-
-;;;
-;;; Mesh
-;;;
-
-;; A complete 3D model composed of many primitives.
-(define-record-type <mesh>
-  (make-mesh name primitives)
-  mesh?
-  (name mesh-name)
-  (primitives mesh-primitives))
-
-(define (draw-mesh mesh state)
-  (let ((render (render-state-renderer state)))
-    (for-each (lambda (primitive) (render primitive state))
-              (mesh-primitives mesh))))
-
 
 ;;;
 ;;; Model Node
@@ -194,15 +114,22 @@
                           (children '()))
   (%make-model-node name mesh matrix world-matrix children))
 
-(define (draw-model-node node state)
+(define (draw-model-node node state view-matrix camera-position ambient-light
+                         lights)
   (for-each (lambda (child)
-              (draw-model-node child state))
+              (draw-model-node child state view-matrix camera-position
+                               ambient-light lights))
             (model-node-children node))
   (let ((mesh (model-node-mesh node)))
     (when mesh
       (render-state-world-model-matrix-mult! state
                                              (model-node-world-matrix node))
-      (draw-mesh mesh state))))
+      (draw-mesh mesh
+                 #:model-matrix (render-state-world-model-matrix state)
+                 #:view-matrix view-matrix
+                 #:camera-position camera-position
+                 #:ambient-light ambient-light
+                 #:lights lights))))
 
 
 ;;;
@@ -225,19 +152,16 @@
 (define %depth-test (make-depth-test))
 
 (define* (draw-model model model-matrix view-matrix camera-position #:key
-                     (lights '())
-                     (ambient-light-color %default-ambient-light-color))
+                     (ambient-light black)
+                     (lights '()))
   (with-graphics-state ((g:depth-test %depth-test)
                         (g:multisample? #t))
     (let ((state (model-render-state model)))
       (render-state-reset! state)
-      (render-state-view-matrix-mult! state view-matrix)
       (render-state-model-matrix-mult! state model-matrix)
-      (set-render-state-camera-position! state camera-position)
-      (set-render-state-lights! state lights)
-      (set-render-state-ambient-light-color! state ambient-light-color)
       ;; TODO: Support drawing non-default scenes.
-      (draw-model-node (model-default-scene model) state))))
+      (draw-model-node (model-default-scene model) state view-matrix
+                       camera-position ambient-light lights))))
 
 
 ;;;
@@ -283,26 +207,32 @@
                 (define (maybe-add-material)
                   (let ((name (assq-ref opts 'name)))
                     (when name
-                      (hash-set! material-map
-                                 name
-                                 (make-phong-material
-                                  #:name name
-                                  #:ambient (assq-ref opts 'ambient)
-                                  #:ambient-map (assq-ref opts 'ambient-map)
-                                  #:use-ambient-map
-                                  (assq-ref opts 'use-ambient-map?)
-                                  #:diffuse (assq-ref opts 'diffuse)
-                                  #:diffuse-map (assq-ref opts 'diffuse-map)
-                                  #:use-diffuse-map
-                                  (assq-ref opts 'use-diffuse-map?)
-                                  #:specular (assq-ref opts 'specular)
-                                  #:specular-map (assq-ref opts 'specular-map)
-                                  #:use-specular-map
-                                  (assq-ref opts 'use-specular-map?)
-                                  #:shininess (assq-ref opts 'shininess)
-                                  #:bump-map (assq-ref opts 'bump-map)
-                                  #:use-bump-map
-                                  (assq-ref opts 'use-bump-map?))))))
+                      (let* ((ambient (assq-ref opts 'ambient-map))
+                             (diffuse (assq-ref opts 'diffuse-map))
+                             (specular (assq-ref opts 'specular-map))
+                             (normals (assq-ref opts 'normal-map))
+                             (properties (make-phong-properties
+                                          #:ambient (assq-ref opts 'ambient)
+                                          #:use-ambient-map
+                                          (assq-ref opts 'use-ambient-map?)
+                                          #:diffuse (assq-ref opts 'diffuse)
+                                          #:use-diffuse-map
+                                          (assq-ref opts 'use-diffuse-map?)
+                                          #:specular (assq-ref opts 'specular)
+                                          #:use-specular-map
+                                          (assq-ref opts 'use-specular-map?)
+                                          #:shininess (assq-ref opts 'shininess)
+                                          #:use-normal-map
+                                          (assq-ref opts 'use-normal-map?)))
+                             (material
+                              (make-material #:name name
+                                             #:shader (phong-shader)
+                                             #:texture-0 ambient
+                                             #:texture-1 diffuse
+                                             #:texture-2 specular
+                                             #:texture-3 normals
+                                             #:properties properties)))
+                        (hash-set! material-map name material)))))
                 (match (read-line port)
                   ((? eof-object?)
                    (maybe-add-material))
@@ -384,15 +314,15 @@
                                      (cons 'use-specular-map? #t)
                                      opts))))
                      (((or "map_Bump" "map_bump" "bump") . args) ; normal map
-                      (let* ((bump-opts (parse-map-args args))
-                             (file (scope-file (assq-ref bump-opts
+                      (let* ((normal-opts (parse-map-args args))
+                             (file (scope-file (assq-ref normal-opts
                                                          'file-name)))
                              (texture (load-image file
                                                   #:min-filter 'linear
                                                   #:mag-filter 'linear
                                                   #:flip? #f)))
-                        (loop (cons* (cons 'bump-map texture)
-                                     (cons 'use-bump-map? #t)
+                        (loop (cons* (cons 'normal-map texture)
+                                     (cons 'use-normal-map? #t)
                                      opts))))
                      (("newmtl" new-name)
                       ;; Begin new material
@@ -408,8 +338,8 @@
                               (specular-map . ,null-texture)
                               (use-specular-map? . #f)
                               (shininess . 1.0)
-                              (bump-map . ,null-texture)
-                              (use-bump-map? . #f))))
+                              (normal-map . ,null-texture)
+                              (use-normal-map? . #f))))
                      (data
                       (format (current-error-port)
                               "warning: ~a:~d: unsupported MTL data: ~s~%"
@@ -626,7 +556,7 @@
                               (or (hash-ref material-map material)
                                   (hash-ref material-map "default"))))))
         ;; Register default material
-        (hash-set! material-map "default" default-phong-material)
+        (hash-set! material-map "default" default-phong-properties)
         ;; Parse file.
         (let loop ((material "default"))
           (match (read-line port)
@@ -684,8 +614,7 @@
                                        #:mesh mesh)))
           (make-model #:name model-name
                       #:scenes (list scene)
-                      #:render-state
-                      (make-render-state draw-primitive/phong)))))))
+                      #:render-state (make-render-state)))))))
 
 
 ;;;
@@ -962,32 +891,38 @@
                     (parse-texture obj "occlusionTexture"))
                    ((emissive-texture emissive-texcoord)
                     (parse-texture obj "emissiveTexture")))
-        (make-pbr-material #:name name
-                           #:base-color-factor base-color-factor
-                           #:base-color-texture base-color-texture
-                           #:base-color-texture-enabled (non-null-texture? base-color-texture)
-                           #:base-color-texcoord base-color-texcoord
-                           #:metallic-factor metallic-factor
-                           #:roughness-factor roughness-factor
-                           #:metallic-roughness-texture metal-rough-texture
-                           #:metallic-roughness-texture-enabled (non-null-texture? metal-rough-texture)
-                           #:metallic-roughness-texcoord metal-rough-texcoord
-                           #:normal-factor normal-factor
-                           #:normal-texture normal-texture
-                           #:normal-texture-enabled (non-null-texture? normal-texture)
-                           #:normal-texcoord normal-texcoord
-                           #:occlusion-texture occlusion-texture
-                           #:occlusion-texture-enabled (non-null-texture? occlusion-texture)
-                           #:occlusion-texcoord occlusion-texcoord
-                           #:emissive-factor emissive-factor
-                           #:emissive-texture emissive-texture
-                           #:emissive-texture-enabled (non-null-texture? emissive-texture)
-                           #:emissive-texcoord emissive-texcoord
-                           #:alpha-mode alpha-mode
-                           #:alpha-cutoff alpha-cutoff
-                           #:double-sided? double-sided?))))
+        (make-material
+         #:name name
+         #:shader (pbr-shader)
+         #:blend-mode (if (= alpha-mode 2) blend:alpha blend:replace)
+         #:cull-face-mode (if double-sided?
+                              no-cull-face-mode
+                              back-cull-face-mode)
+         #:texture-0 base-color-texture
+         #:texture-1 metal-rough-texture
+         #:texture-2 normal-texture
+         #:texture-3 occlusion-texture
+         #:texture-4 emissive-texture
+         #:properties (make-pbr-properties
+                       #:base-color-factor base-color-factor
+                       #:base-color-texture-enabled (non-null-texture? base-color-texture)
+                       #:base-color-texcoord base-color-texcoord
+                       #:metallic-factor metallic-factor
+                       #:roughness-factor roughness-factor
+                       #:metallic-roughness-texture-enabled (non-null-texture? metal-rough-texture)
+                       #:metallic-roughness-texcoord metal-rough-texcoord
+                       #:normal-factor normal-factor
+                       #:normal-texture-enabled (non-null-texture? normal-texture)
+                       #:normal-texcoord normal-texcoord
+                       #:occlusion-texture-enabled (non-null-texture? occlusion-texture)
+                       #:occlusion-texcoord occlusion-texcoord
+                       #:emissive-factor emissive-factor
+                       #:emissive-texture-enabled (non-null-texture? emissive-texture)
+                       #:emissive-texcoord emissive-texcoord
+                       #:alpha-mode alpha-mode
+                       #:alpha-cutoff alpha-cutoff)))))
   (define (attribute-name->index name)
-    (let ((shader (graphics-variable-ref pbr-shader)))
+    (let ((shader (pbr-shader)))
       (match name
         ("POSITION"
          (attribute-location
@@ -1026,7 +961,7 @@
                      (#f #f)
                      (n (vector-ref accessors n))))
           (material (match (number-ref/optional obj "material")
-                      (#f default-pbr-material)
+                      (#f default-pbr-properties)
                       (n (vector-ref materials n))))
           (mode (match (or (number-ref/optional obj "mode") 4)
                   (0 'points)
@@ -1173,5 +1108,4 @@
           (error "unsupported glTF version" version))
         (make-model #:name (basename file-name)
                     #:scenes (list default-scene)
-                    #:render-state
-                    (make-render-state draw-primitive/pbr))))))
+                    #:render-state (make-render-state))))))
diff --git a/chickadee/graphics/pbr.scm b/chickadee/graphics/pbr.scm
index 0977579..16b5878 100644
--- a/chickadee/graphics/pbr.scm
+++ b/chickadee/graphics/pbr.scm
@@ -32,119 +32,77 @@
   #:use-module (chickadee graphics shader)
   #:use-module (chickadee graphics texture)
   #:use-module (srfi srfi-9)
-  #:export (make-pbr-material
-            pbr-material?
-            pbr-material-name
-            pbr-material-base-color-factor
-            pbr-material-base-color-texture
-            pbr-material-base-color-texture-enabled?
-            pbr-material-base-color-texcoord
-            pbr-material-metallic-factor
-            pbr-material-roughness-factor
-            pbr-material-metallic-roughness-texture
-            pbr-material-metallic-roughness-texture-enabled?
-            pbr-material-metallic-roughness-texcoord
-            pbr-material-normal-factor
-            pbr-material-normal-texture
-            pbr-material-normal-texture-enabled?
-            pbr-material-normal-texcoord
-            pbr-material-occlusion-texture
-            pbr-material-occlusion-texture-enabled?
-            pbr-material-occlusion-texcoord
-            pbr-material-emissive-factor
-            pbr-material-emissive-texture
-            pbr-material-emissive-texture-enabled?
-            pbr-material-emissive-texcoord
-            pbr-material-alpha-mode
-            pbr-material-alpha-cutoff
-            pbr-material-double-sided?
-            default-pbr-material
-            pbr-shader
-            shader-apply/pbr))
+  #:export (make-pbr-properties
+            pbr-properties?
+            pbr-properties-base-color-factor
+            pbr-properties-base-color-texture-enabled?
+            pbr-properties-base-color-texcoord
+            pbr-properties-metallic-factor
+            pbr-properties-roughness-factor
+            pbr-properties-metallic-roughness-texture-enabled?
+            pbr-properties-metallic-roughness-texcoord
+            pbr-properties-normal-factor
+            pbr-properties-normal-texture-enabled?
+            pbr-properties-normal-texcoord
+            pbr-properties-occlusion-texture-enabled?
+            pbr-properties-occlusion-texcoord
+            pbr-properties-emissive-factor
+            pbr-properties-emissive-texture-enabled?
+            pbr-properties-emissive-texcoord
+            pbr-properties-alpha-mode
+            pbr-properties-alpha-cutoff
+            default-pbr-properties
+            pbr-shader))
 
-(define-shader-type <pbr-material>
-  make-pbr-material
-  pbr-material?
-  (local-field name pbr-material-name)
-  (float-vec3 base-color-factor pbr-material-base-color-factor)
-  (local-field base-color-texture pbr-material-base-color-texture)
-  (bool base-color-texture-enabled pbr-material-base-color-texture-enabled?)
-  (int base-color-texcoord pbr-material-base-color-texcoord)
-  (float metallic-factor pbr-material-metallic-factor)
-  (float roughness-factor pbr-material-roughness-factor)
-  (local-field metallic-roughness-texture pbr-material-metallic-roughness-texture)
-  (bool metallic-roughness-texture-enabled pbr-material-metallic-roughness-texture-enabled?)
-  (int metallic-roughness-texcoord pbr-material-metallic-roughness-texcoord)
-  (float-vec3 normal-factor pbr-material-normal-factor)
-  (local-field normal-texture pbr-material-normal-texture)
-  (bool normal-texture-enabled pbr-material-normal-texture-enabled)
-  (int normal-texcoord pbr-material-normal-texcoord)
-  (local-field occlusion-texture pbr-material-occlusion-texture)
-  (bool occlusion-texture-enabled pbr-material-occlusion-texture-enabled)
-  (int occlusion-texcoord pbr-material-occlusion-texcoord)
-  (float-vec3 emissive-factor pbr-material-emissive-factor)
-  (local-field emissive-texture pbr-material-emissive-texture)
-  (bool emissive-texture-enabled pbr-material-emissive-texture-enabled)
-  (int emissive-texcoord pbr-material-emissive-texcoord)
-  (int alpha-mode pbr-material-alpha-mode)
-  (float alpha-cutoff pbr-material-alpha-cutoff)
-  (local-field double-sided? pbr-material-double-sided?))
+(define-shader-type <pbr-properties>
+  make-pbr-properties
+  pbr-properties?
+  (float-vec3 base-color-factor pbr-properties-base-color-factor)
+  (bool base-color-texture-enabled pbr-properties-base-color-texture-enabled?)
+  (int base-color-texcoord pbr-properties-base-color-texcoord)
+  (float metallic-factor pbr-properties-metallic-factor)
+  (float roughness-factor pbr-properties-roughness-factor)
+  (bool metallic-roughness-texture-enabled pbr-properties-metallic-roughness-texture-enabled?)
+  (int metallic-roughness-texcoord pbr-properties-metallic-roughness-texcoord)
+  (float-vec3 normal-factor pbr-properties-normal-factor)
+  (bool normal-texture-enabled pbr-properties-normal-texture-enabled)
+  (int normal-texcoord pbr-properties-normal-texcoord)
+  (bool occlusion-texture-enabled pbr-properties-occlusion-texture-enabled)
+  (int occlusion-texcoord pbr-properties-occlusion-texcoord)
+  (float-vec3 emissive-factor pbr-properties-emissive-factor)
+  (bool emissive-texture-enabled pbr-properties-emissive-texture-enabled)
+  (int emissive-texcoord pbr-properties-emissive-texcoord)
+  (int alpha-mode pbr-properties-alpha-mode)
+  (float alpha-cutoff pbr-properties-alpha-cutoff))
 
-(define default-pbr-material
-  (make-pbr-material #:name "default"
-                     #:base-color-factor #v(1.0 1.0 1.0)
-                     #:base-color-texture null-texture
+(define default-pbr-properties
+  (make-pbr-properties #:base-color-factor #v(1.0 1.0 1.0)
                      #:base-color-texture-enabled #f
                      #:base-color-texcoord 0
                      #:metallic-factor 1.0
                      #:roughness-factor 1.0
-                     #:metallic-roughness-texture null-texture
                      #:metallic-roughness-texture-enabled #f
                      #:metallic-roughness-texcoord 0
                      #:normal-factor #v(1.0 1.0 1.0)
-                     #:normal-texture null-texture
                      #:normal-texture-enabled #f
                      #:normal-texcoord 0
-                     #:occlusion-texture null-texture
                      #:occlusion-texture-enabled #f
                      #:occlusion-texcoord 0
                      #:emissive-factor #v(1.0 1.0 1.0)
-                     #:emissive-texture null-texture
                      #:emissive-texture-enabled #f
                      #:emissive-texcoord 0
                      #:alpha-mode 0
-                     #:alpha-cutoff 0.5
-                     #:double-sided? #f))
+                     #:alpha-cutoff 0.5))
 
-(define-graphics-variable pbr-shader
-  (load-shader (scope-datadir "shaders/pbr-vert.glsl")
-               (scope-datadir "shaders/pbr-frag.glsl")))
+(define %pbr-shader
+  (delay (load-shader (scope-datadir "shaders/pbr-vert.glsl")
+                      (scope-datadir "shaders/pbr-frag.glsl"))))
 
-(define (shader-apply/pbr vertex-array material model-matrix view-matrix
-                          camera-position lights ambient-light-color)
-  (let* ((shader (graphics-variable-ref pbr-shader))
-         (vattrs (vertex-array-attributes vertex-array))
-         (sattrs (shader-attributes shader)))
-    (with-graphics-state ((g:blend-mode (if (= (pbr-material-alpha-mode material) 2)
-                                            blend:alpha
-                                            blend:replace))
-                          (g:cull-face-mode (if (pbr-material-double-sided? material)
-                                                no-cull-face-mode
-                                                back-cull-face-mode))
-                          (g:texture-0 (pbr-material-base-color-texture material))
-                          (g:texture-1 (pbr-material-metallic-roughness-texture material))
-                          (g:texture-2 (pbr-material-normal-texture material))
-                          (g:texture-3 (pbr-material-occlusion-texture material))
-                          (g:texture-4 (pbr-material-emissive-texture material)))
-      (shader-apply shader vertex-array
-                    #:model model-matrix
-                    #:view view-matrix
-                    #:projection (current-projection)
-                    #:vertex-colored (buffer-view?
-                                      (assv-ref vattrs
-                                                (attribute-location
-                                                 (hash-ref sattrs "color0"))))
-                    #:camera-position camera-position
-                    #:material material
-                    #:ambient-light-color ambient-light-color
-                    #:lights lights))))
+(define (pbr-shader)
+  (force %pbr-shader))
+
+;; TODO: Handle vertex colors
+;; (buffer-view?
+;;  (assv-ref vattrs
+;;            (attribute-location
+;;             (hash-ref sattrs "color0"))))
diff --git a/chickadee/graphics/phong.scm b/chickadee/graphics/phong.scm
index 5288075..edb8686 100644
--- a/chickadee/graphics/phong.scm
+++ b/chickadee/graphics/phong.scm
@@ -30,83 +30,56 @@
   #:use-module (chickadee graphics shader)
   #:use-module (chickadee graphics texture)
   #:use-module (srfi srfi-9)
-  #:export (make-phong-material
-            phong-material?
-            phong-material-name
-            phong-material-ambient
-            phong-material-ambient-map
-            phong-material-use-ambient-map?
-            phong-material-diffuse
-            phong-material-diffuse-map
-            phong-material-use-diffuse-map?
-            phong-material-specular
-            phong-material-specular-map?
-            phong-material-use-specular-map?
-            phong-material-specular-exponent
-            phong-material-bump-map
-            phong-material-use-bump-map?
-            default-phong-material
-            load-phong-shader
-            shader-apply/phong))
+  #:export (make-phong-properties
+            phong-properties?
+            phong-properties-name
+            phong-properties-ambient
+            phong-properties-use-ambient-map?
+            phong-properties-diffuse
+            phong-properties-use-diffuse-map?
+            phong-properties-specular
+            phong-properties-specular-map?
+            phong-properties-use-specular-map?
+            phong-properties-specular-exponent
+            phong-properties-use-normal-map?
+            default-phong-properties
+            phong-shader))
 
 
 ;;;
-;;; Phong Material
+;;; Phong Properties
 ;;;
 
-(define-shader-type <phong-material>
-  make-phong-material
-  phong-material?
-  (local-field name phong-material-name)
-  (float-vec3 ambient phong-material-ambient)
-  (local-field ambient-map phong-material-ambient-map)
-  (bool use-ambient-map phong-material-use-ambient-map?)
-  (float-vec3 diffuse phong-material-diffuse)
-  (local-field diffuse-map phong-material-diffuse-map)
-  (bool use-diffuse-map phong-material-use-diffuse-map?)
-  (float-vec3 specular phong-material-specular)
-  (local-field specular-map phong-material-specular-map)
-  (bool use-specular-map phong-material-use-specular-map?)
-  (float shininess phong-material-shininess)
-  (local-field bump-map phong-material-bump-map)
-  (bool use-bump-map phong-material-use-bump-map?))
+(define-shader-type <phong-properties>
+  make-phong-properties
+  phong-properties?
+  (float-vec3 ambient phong-properties-ambient)
+  (bool use-ambient-map phong-properties-use-ambient-map?)
+  (float-vec3 diffuse phong-properties-diffuse)
+  (bool use-diffuse-map phong-properties-use-diffuse-map?)
+  (float-vec3 specular phong-properties-specular)
+  (bool use-specular-map phong-properties-use-specular-map?)
+  (float shininess phong-properties-shininess)
+  (bool use-normal-map phong-properties-use-normal-map?))
 
-(define default-phong-material
-  (make-phong-material #:name "default"
-                       #:ambient (vec3 0.5 0.5 0.5)
-                       #:ambient-map null-texture
-                       #:use-ambient-map #f
-                       #:diffuse (vec3 0.8 0.8 0.8)
-                       #:diffuse-map null-texture
-                       #:use-diffuse-map #f
-                       #:specular (vec3 0.3 0.3 0.3)
-                       #:specular-map null-texture
-                       #:use-specular-map #f
-                       #:shininess 32.0
-                       #:bump-map null-texture
-                       #:use-bump-map #f))
+(define default-phong-properties
+  (make-phong-properties #:ambient (vec3 0.5 0.5 0.5)
+                         #:use-ambient-map #f
+                         #:diffuse (vec3 0.8 0.8 0.8)
+                         #:use-diffuse-map #f
+                         #:specular (vec3 1.0 1.0 1.0)
+                         #:use-specular-map #f
+                         #:shininess 32.0
+                         #:use-normal-map #f))
 
 
 ;;;
 ;;; Phong Shader
 ;;;
 
-(define-graphics-variable phong-shader
-  (load-shader (scope-datadir "shaders/phong-vert.glsl")
-               (scope-datadir "shaders/phong-frag.glsl")))
+(define %phong-shader
+  (delay (load-shader (scope-datadir "shaders/phong-vert.glsl")
+                      (scope-datadir "shaders/phong-frag.glsl"))))
 
-(define (shader-apply/phong vertex-array material model-matrix view-matrix
-                            camera-position lights ambient-light-color)
-  (let ((shader (graphics-variable-ref phong-shader)))
-    (with-graphics-state ((g:texture-0 (phong-material-ambient-map material))
-                          (g:texture-1 (phong-material-diffuse-map material))
-                          (g:texture-2 (phong-material-specular-map material))
-                          (g:texture-3 (phong-material-bump-map material)))
-      (shader-apply shader vertex-array
-                    #:model model-matrix
-                    #:view view-matrix
-                    #:projection (current-projection)
-                    #:material material
-                    #:camera-position camera-position
-                    #:ambient-light-color ambient-light-color
-                    #:lights lights))))
+(define (phong-shader)
+  (force %phong-shader))
diff --git a/data/shaders/pbr-frag.glsl b/data/shaders/pbr-frag.glsl
index a941a29..478c40a 100644
--- a/data/shaders/pbr-frag.glsl
+++ b/data/shaders/pbr-frag.glsl
@@ -53,7 +53,7 @@ out vec4 fragColor;
 
 uniform Material material;
 uniform Light lights[MAX_LIGHTS];
-uniform vec4 ambientLightColor;
+uniform vec4 ambientLight;
 uniform bool vertexColored;
 uniform vec3 cameraPosition;
 uniform sampler2D baseColorTexture;
@@ -386,7 +386,7 @@ void main(void) {
   // is dampened by the ambient occlusion factor.
   //
   // TODO: Use image based lighting.
-  color += ambientLightColor.rgb * albedo * ambientOcclusion;
+  color += ambientLight.rgb * albedo * ambientOcclusion;
   // Apply Reinhard tone mapping to convert our high dynamic range
   // color value to low dynamic range.  All of the lighting
   // calculations stacked on top of each other is likely to create
diff --git a/data/shaders/phong-frag.glsl b/data/shaders/phong-frag.glsl
index 7cab3f8..363c4e7 100644
--- a/data/shaders/phong-frag.glsl
+++ b/data/shaders/phong-frag.glsl
@@ -2,17 +2,13 @@
 
 struct Material {
   vec3 ambient;
-  sampler2D ambientMap;
   bool useAmbientMap;
   vec3 diffuse;
-  sampler2D diffuseMap;
   bool useDiffuseMap;
   vec3 specular;
-  sampler2D specularMap;
   bool useSpecularMap;
   float shininess;
-  sampler2D bumpMap;
-  bool useBumpMap;
+  bool useNormalMap;
 };
 
 struct Light {
@@ -40,10 +36,14 @@ in vec2 fragTex;
 out vec4 fragColor;
 #endif
 
+uniform sampler2D ambientMap;
+uniform sampler2D diffuseMap;
+uniform sampler2D specularMap;
+uniform sampler2D normalMap;
 uniform Material material;
 uniform Light lights[MAX_LIGHTS];
 uniform vec3 cameraPosition;
-uniform vec4 ambientLightColor;
+uniform vec4 ambientLight;
 
 const float GAMMA = 2.2;
 
@@ -54,10 +54,6 @@ vec2 texture(sampler2D tex, vec2 coord) {
 }
 #endif
 
-float posDot(vec3 v1, vec3 v2) {
-  return max(dot(v1, v2), 0.0);
-}
-
 vec3 gammaCorrect(vec3 color) {
   return pow(color, vec3(1.0 / GAMMA));
 }
@@ -105,7 +101,7 @@ vec3 lightRadiance(Light light, vec3 direction) {
 
 vec3 materialAmbient() {
   if(material.useAmbientMap) {
-    return texture(material.ambientMap, fragTex).rgb;
+    return texture(ambientMap, fragTex).rgb;
   } else {
     return material.ambient;
   }
@@ -113,7 +109,7 @@ vec3 materialAmbient() {
 
 vec3 materialDiffuse() {
   if(material.useDiffuseMap) {
-    vec4 color = texture(material.diffuseMap, fragTex);
+    vec4 color = texture(diffuseMap, fragTex);
     // discard transparent fragments.
     if(color.a == 0.0) {
       discard;
@@ -126,18 +122,18 @@ vec3 materialDiffuse() {
 
 vec3 materialSpecular() {
   if(material.useSpecularMap) {
-    return texture(material.specularMap, fragTex).rgb;
+    return texture(specularMap, fragTex).rgb;
   } else {
     return material.specular;
   }
 }
 
 vec3 materialNormal() {
-  if(material.useBumpMap) {
+  if(material.useNormalMap) {
     // Compute tangent space using fragment data rather than relying
     // on tangent attributes.  See:
     // http://www.thetenthplanet.de/archives/1180
-    vec3 tangentNormal = normalize(texture(material.bumpMap, fragTex).xyz * 2.0 - 1.0);
+    vec3 tangentNormal = normalize(texture(normalMap, fragTex).xyz * 2.0 - 1.0);
     vec3 q1 = dFdx(fragWorldPos);
     vec3 q2 = dFdy(fragWorldPos);
     vec2 st1 = dFdx(fragTex);
@@ -156,8 +152,8 @@ vec3 materialNormal() {
 void main() {
   vec3 viewDir = normalize(cameraPosition - fragWorldPos);
   vec3 ambientOcclusion = materialAmbient();
-  vec3 baseDiffuseColor = materialDiffuse();
-  vec3 baseSpecularColor = materialSpecular();
+  vec3 diffuseColor = materialDiffuse();
+  vec3 specularColor = materialSpecular();
   vec3 normal = materialNormal();
   vec3 color = vec3(0.0);
 
@@ -170,18 +166,17 @@ void main() {
     }
 
     vec3 lightDir = lightDirection(light);
-    vec3 radiance = lightRadiance(light, lightDir);
-    float diffuseFactor = posDot(lightDir, normal);
-    vec3 reflectDir = reflect(-lightDir, normal);
-    vec3 diffuseColor = baseDiffuseColor * diffuseFactor;
     vec3 halfVector = normalize(lightDir + viewDir);
-    float specularFactor = pow(posDot(halfVector, normal), material.shininess);
-    vec3 specularColor = baseSpecularColor * specularFactor;
-    color += (diffuseColor + specularColor) * radiance;
+    vec3 radiance = lightRadiance(light, lightDir);
+    float lambert = clamp(dot(normal, lightDir), 0.0, 1.0);
+    vec3 diffuseLight = radiance * lambert;
+    float specularFactor = clamp(dot(halfVector, normal), 0.0, 1.0) * float(lambert > 0.0);
+    vec3 specularLight = radiance * pow(specularFactor, material.shininess);
+    color += diffuseLight * diffuseColor + specularLight * specularColor;
   }
 
   // Apply ambient lighting.
-  vec3 ambientColor = baseDiffuseColor * ambientLightColor.rgb * ambientOcclusion;
+  vec3 ambientColor = diffuseColor * ambientLight.rgb * ambientOcclusion;
   color += ambientColor;
 
   // Apply gamma correction and HDR tone mapping to get the final