1 files changed, 91 insertions, 0 deletions
diff --git a/src/interactive-units/text.lisp b/src/interactive-units/text.lisp
new file mode 100644
index 0000000..f439621
--- /dev/null
+++ b/src/interactive-units/text.lisp
@@ -0,0 +1,91 @@
+;;;; units/text.lisp
+
+(in-package #:wheelwork)
+
+(defclass/std text (unit interactive)
+  ((font :with :ri :std (error "A font is required") :type font)
+   (content :with :ri :std "")
+   (color :with :std #(1.0 1.0 1.0 1.0))
+   (vao elem-count newlines :r)
+   (shader :with :static :r)))
+
+(defmethod model-matrix ((text text))
+  (let ((m (mat:meye 4)))
+    (with-slots (font newlines x y base-width base-height scale-x scale-y rotation) text 
+      (let* ((text-height
+               (cl-fond:text-height (font-object font)))
+             (baseline-offset
+              (* newlines text-height))
+             (rotation-baseline-offset
+               (* 2 newlines text-height )))
+        (mat:nmtranslate m (vec:vec x
+                                    (+ y
+                                       (*
+                                        scale-y
+                                        baseline-offset))
+                                    0.0))
+
+        (mat:nmtranslate m (vec:v* 0.5 (vec:vec (* scale-x base-width)
+                                                (* scale-y (- base-height rotation-baseline-offset) )
+                                                0.0)))
+        (mat:nmrotate  m vec:+vz+ rotation)
+        (mat:nmtranslate m (vec:v* -0.5 (vec:vec (* scale-x base-width )
+                                                 (* scale-y (- base-height rotation-baseline-offset))
+                                                 0.0))))
+      
+      (mat:nmscale m (vec:vec scale-x scale-y 1.0))
+      m)))
+
+(defmethod initialize-instance :after ((text text) &key)
+  (with-slots (content newlines font vao elem-count shader base-width base-height scale-x scale-y) text
+    (unless shader
+      (setf shader
+            (create-shader
+             '(:vertex
+               ((vert :vec2) (col :vec2))
+               ((transform :mat4))
+               ((values
+                 (* transform (vari:vec4 vert 0.0 1.0))
+                 col)))
+             '(:fragment
+               ((tc :vec2))
+               ((tex :sampler-2d)
+                (color :vec4))
+               ((* color (aref (vari:texture tex tc) 0)))))))
+    (multiple-value-bind (vao% count%) (cl-fond:compute-text (font-object font) content)
+      (setf vao vao%
+            elem-count count%))
+    (setf newlines (count #\newline content))
+    (hq:with-plist (l r) (cl-fond:compute-extent (font-object font) content)
+      (setf base-width (- r l)
+            base-height (* (cl-fond:text-height (font-object font))
+                           (1+ newlines))))))
+
+(defmethod cleanup ((text text))
+  (with-slots (vao shader) text
+    (gl:delete-vertex-arrays (list vao))
+    (when shader
+      (gl:delete-program shader))
+    (setf vao nil
+          shader nil)))
+
+(defmethod render ((text text))
+  (with-slots (shader font vao elem-count color) text
+    (gl:use-program shader)
+    (gl:active-texture 0)
+    (gl:bind-texture :texture-2d (cl-fond:texture (font-object font)))
+    (gl:program-uniform-matrix-4fv
+     shader
+     (gl:get-uniform-location shader "TRANSFORM")
+     (projected-matrix text))
+    (gl:program-uniformi
+     shader
+     (gl:get-uniform-location shader "TEX")
+     0)
+    (gl:program-uniformfv
+     shader
+     (gl:get-uniform-location shader "COLOR")
+     color)
+    (gl:bind-vertex-array vao)
+    (%gl:draw-elements :triangles elem-count :unsigned-int 0)
+    (gl:bind-vertex-array 0)))