render: font: Simplify implementation with texture regions.

* chickadee/render/font.scm (<font-char>) [texture, region]: Remove.
[texture-region]: New field.
(load-font): Use texture regions.
(draw-text): Render using texture regions.

1 files changed, 13 insertions, 20 deletions

diff --git a/chickadee/render/font.scm b/chickadee/render/font.scm
index fab1977..c2c1bea 100644
--- a/chickadee/render/font.scm
+++ b/chickadee/render/font.scm
@@ -44,11 +44,10 @@
             draw-text))
 
 (define-record-type <font-char>
-  (make-font-char id texture region offset dimensions advance)
+  (make-font-char id texture-region offset dimensions advance)
   font-char?
   (id font-char-id)
-  (texture font-char-texture)
-  (region font-char-region)
+  (texture-region font-char-texture-region)
   (offset font-char-offset)
   (dimensions font-char-dimensions)
   (advance font-char-advance))
@@ -112,12 +111,9 @@
                                       (attr node 'yoffset string->number)))
                          (x-advance (attr node 'xadvance string->number))
                          (page (or (attr node 'page string->number) 0))
-                         (region (make-rect (x->s x)
-                                            (y->t y)
-                                            (x->s width)
-                                            (y->t height)))
+                         (region (make-texture-region (hash-ref pages page)
+                                                      x y width height))
                          (char (make-font-char id
-                                               (hash-ref pages page)
                                                region
                                                (vec2 x-offset y-offset)
                                                (vec2 width height)
@@ -161,8 +157,8 @@
   (hashv-ref (font-chars font) char))
 
 (define draw-text
-  (let ((p (vec2 0.0 0.0))
-        (rect (make-rect 0.0 0.0 0.0 0.0)))
+  (let ((cursor (vec2 0.0 0.0))
+        (char-pos (vec2 0.0 0.0)))
     (lambda* (font text position #:key scale rotation (blend-mode 'alpha))
       "Draw the string TEXT with the first character starting at
 POSITION using FONT."
@@ -171,21 +167,18 @@ POSITION using FONT."
         (let* ((char (font-ref font c))
                (dimensions (font-char-dimensions char))
                (offset (font-char-offset char)))
-          (set-rect-x! rect (+ (vec2-x p) (vec2-x offset)))
-          (set-rect-y! rect (+ (vec2-y p) (vec2-y offset)))
-          (set-rect-width! rect (vec2-x dimensions))
-          (set-rect-height! rect (vec2-y dimensions))
-          (draw-sprite (font-char-texture char)
-                       rect
-                       #:texcoords (font-char-region char)
+          (set-vec2-x! char-pos (+ (vec2-x cursor) (vec2-x offset)))
+          (set-vec2-y! char-pos (+ (vec2-y cursor) (vec2-y offset)))
+          (draw-sprite (font-char-texture-region char)
+                       char-pos
                        #:scale scale
                        #:rotation rotation
                        #:blend-mode blend-mode)
           ;; Move forward to where the next character needs to be drawn.
-          (set-vec2-x! p
-                       (+ (vec2-x p)
+          (set-vec2-x! cursor
+                       (+ (vec2-x cursor)
                           (vec2-x
                            (font-char-advance char))))))
-      (vec2-copy! position p) ; initialize position
+      (vec2-copy! position cursor) ; initialize position
       (with-batched-sprites
        (string-for-each render-char text)))))