From eb480bf15284e973bd37c5fc095c1abd8062e0c5 Mon Sep 17 00:00:00 2001
From: Gabriel Pariat <gabriel@pariatech.com>
Date: Wed, 27 Apr 2022 07:32:43 -0400
Subject: [PATCH] Triangle de couleur

---
 src/renderer.lisp | 36 +++++++++++++++++++-----------------
 1 file changed, 19 insertions(+), 17 deletions(-)

diff --git a/src/renderer.lisp b/src/renderer.lisp
index 07df1f0..b80ec1f 100644
--- a/src/renderer.lisp
+++ b/src/renderer.lisp
@@ -4,13 +4,14 @@
 (defparameter *vertex-shader-source* '("
 #version 330 core
 layout (location = 0) in vec3 aPos;
+layout (location = 1) in vec3 aColor;
 
-out vec4 vertexColor;
+out vec3 ourColor;
 
 void main()
 {
-    gl_Position = vec4(aPos.x, aPos.y, aPos.z, 1.0);
-    vertexColor = vec4(0.5, 0.0, 0.0, 1.0);
+    gl_Position = vec4(aPos, 1.0);
+    ourColor = aColor;
 }
 "))
 
@@ -18,12 +19,11 @@ void main()
 #version 330 core
 out vec4 FragColor;
 
-// in vec4 vertexColor;
-uniform vec4 ourColor;
+in vec3 ourColor;
 
 void main()
 {
-    FragColor = ourColor;
+    FragColor = vec4(ourColor, 1.0);
 }
 "))
 
@@ -54,26 +54,30 @@ void main()
     (gl:bind-buffer :array-buffer *vbo*)
     (gl:bind-buffer :element-array-buffer *ebo*)
 
-    (let* ((vertices #( 0.5  0.5 0.0
-		       0.5 -0.5 0.0
-		      -0.5 -0.5 0.0
-		      -0.5  0.5 0.0))
+    (let* ((vertices #( 0.5 -0.5 0.0 1.0 0.0 0.0
+		       -0.5 -0.5 0.0 0.0 1.0 0.0
+		        0.0  0.5 0.0 0.0 0.0 1.0))
 	   (arr (gl:alloc-gl-array :float (length vertices))))
       (dotimes (i (length vertices))
 	(setf (gl:glaref arr i) (aref vertices i)))
       (gl:buffer-data :array-buffer :static-draw arr)
       (gl:free-gl-array arr))
 
-    (let* ((indices #(0 1 3
-		      1 2 3))
+    (let* ((indices #(0 1 2))
 	   (arr (gl:alloc-gl-array :int (length indices))))
       (dotimes (i (length indices))
 	(setf (gl:glaref arr i) (aref indices i)))
       (gl:buffer-data :element-array-buffer :static-draw arr)
       (gl:free-gl-array arr))
 
-    (gl:vertex-attrib-pointer 0 3 :float nil 0 (cffi:null-pointer))
-    (gl:enable-vertex-attrib-array 0)))
+    (gl:vertex-attrib-pointer 0 3 :float nil
+			      (* 6 (cffi:foreign-type-size :float))
+			      (cffi:null-pointer))
+    (gl:enable-vertex-attrib-array 0)
+    (gl:vertex-attrib-pointer 1 3 :float nil
+			      (* 6 (cffi:foreign-type-size :float))
+			      (cffi:make-pointer (* 3 (cffi:foreign-type-size :float))))
+    (gl:enable-vertex-attrib-array 1)))
 
 (defun enable-wireframe ()
  (gl:polygon-mode :front-and-back :line))
@@ -95,10 +99,8 @@ void main()
   ;;   (gl:rect -25 -25 25 25))
 
   (gl:use-program *shader-program*)
-  (gl:uniformf (gl:get-uniform-location *shader-program* "ourColor")
-	       0.0 (+ (/ (sin (glfw:get-time)) 2) 0.5) 0.0 1.0)
   (gl:bind-vertex-array *vao*)
-  (gl:draw-elements :triangles (gl:make-null-gl-array :unsigned-int) :count 6)
+  (gl:draw-elements :triangles (gl:make-null-gl-array :unsigned-int) :count 3)
   (gl:bind-vertex-array 0)
 
   (glfw:swap-buffers))