1 files changed, 71 insertions, 0 deletions
diff --git a/src/interactive-units/bitmap.lisp b/src/interactive-units/bitmap.lisp
new file mode 100644
index 0000000..95dfff5
--- /dev/null
+++ b/src/interactive-units/bitmap.lisp
@@ -0,0 +1,71 @@
+;;;; bitmap.lisp
+
+(in-package #:wheelwork)
+
+(defclass/std bitmap (unit interactive)
+  ((texture :ri :std (error "A bitmap requires a texture."))
+   (vao shader :with :r :static)))
+
+(defmethod initialize-instance :after ((bitmap bitmap) &key)
+  (with-slots (vao shader base-width base-height texture) bitmap
+    (setf base-height (texture-height texture)
+          base-width (texture-width texture))
+    (unless shader
+      (setf shader
+            (create-shader
+             '(:vertex
+               ((vert :vec2))
+               ((transform :mat4))
+               ((values
+                 (* transform (vari:vec4 vert 0.0 1.0))
+                 vert))) ;color
+             '(:fragment
+               ((tc :vec2))
+               ((tex :sampler-2d))
+               ((let ((frag  (vari:texture tex tc)))
+                  (if (< (aref frag 3) 0.01)
+                      (vari:discard)
+                      frag))))))
+      (gl:program-uniformi
+       shader
+       (gl:get-uniform-location shader "TEX")
+       0))
+    (unless vao
+      (setf vao (gl:gen-vertex-array))
+      (gl:bind-vertex-array vao)
+      (let ((vbo (gl:gen-buffer)))
+        (with-gl-array (verts :float
+                              0.0 1.0 
+                              1.0 0.0 
+                              0.0 0.0 
+                              
+                              0.0 1.0 
+                              1.0 1.0 
+                              1.0 0.0 )
+          (gl:bind-buffer :array-buffer vbo)
+          (gl:buffer-data :array-buffer :static-draw verts)))
+      (gl:enable-vertex-attrib-array 0)
+      (gl:vertex-attrib-pointer 0 2 :float 0 (* +float-size+ 2) 0)
+      (gl:bind-buffer :array-buffer 0)
+      (gl:bind-vertex-array 0))))
+
+(defmethod cleanup ((bitmap bitmap))
+  (with-slots (vao shader) bitmap
+    (when vao
+      (gl:delete-vertex-arrays (list vao)))
+    (when shader
+      (gl:delete-program shader))
+    (setf vao nil
+          shader nil)))
+(defmethod render ((bitmap bitmap))
+  (with-slots (texture vao shader) bitmap
+    (gl:active-texture 0)
+    (gl:bind-texture :texture-2d (texture-id texture))
+    (gl:use-program shader)
+    (gl:program-uniform-matrix-4fv
+     shader
+     (gl:get-uniform-location shader "TRANSFORM")
+     (projected-matrix bitmap))
+    (gl:bind-vertex-array vao)    
+    (gl:draw-arrays :triangles 0 6)
+    (gl:bind-vertex-array 0)))