example.rb

@@ -2,9 +2,6 @@
 
 require 'sfml/all'
 require 'opengl'
-require 'glutil'
-
-include GLUtil
 
 class Example
   include SFML
@@ -18,7 +15,8 @@ class Example
   end
 
   def load_shaders
-    v_shader = GLShader.new(GL_VERTEX_SHADER, <<-EOS)
+    v_id = glCreateShader(GL_VERTEX_SHADER)
+    glShaderSource(v_id, <<-EOS)
       uniform vec2 offset;
       uniform vec2 screen_size;
       attribute vec2 pos;
@@ -33,8 +31,13 @@ class Example
         gl_Position = pos_i;
       }
     EOS
+    glCompileShader(v_id)
+    unless glGetShaderiv(v_id, GL_COMPILE_STATUS)
+      raise glGetShaderInfoLog(v_id)
+    end
 
-    f_shader = GLShader.new(GL_FRAGMENT_SHADER, <<-EOS)
+    f_id = glCreateShader(GL_FRAGMENT_SHADER)
+    glShaderSource(f_id, <<-EOS)
       varying vec4 pos_i;
 
       void main()
@@ -44,11 +47,22 @@ class Example
                             0, 1);
       }
     EOS
+    glCompileShader(f_id)
+    unless glGetShaderiv(f_id, GL_COMPILE_STATUS)
+      raise glGetShaderInfoLog(f_id)
+    end
 
-    program = GLProgram.new([v_shader, f_shader])
-    $offset_loc = program.get_uniform_location("offset")
-    $screen_size_loc = program.get_uniform_location("screen_size")
-    program.use
+    p_id = glCreateProgram()
+    glAttachShader(p_id, v_id)
+    glAttachShader(p_id, f_id)
+    glLinkProgram(p_id)
+    unless glGetProgramiv(p_id, GL_LINK_STATUS)
+      raise glGetProgramInfoLog(p_id)
+    end
+    $offset_loc = glGetUniformLocation(p_id, "offset")
+    $screen_size_loc = glGetUniformLocation(p_id, "screen_size")
+
+    glUseProgram(p_id)
   end
 
   def create_window
@@ -67,7 +81,9 @@ class Example
                   -0.02, 0.02,
                   -0.02, -0.02,
                   0.02, -0.02].pack("f*")
-    buffer = GLBuffer.new(GL_ARRAY_BUFFER, GL_STATIC_DRAW, quad_attrs, 2 * 4 * 4)
+    b_id = glGenBuffers(1).first
+    glBindBuffer(GL_ARRAY_BUFFER, b_id);
+    glBufferData(GL_ARRAY_BUFFER, 2 * 4 * 4, quad_attrs, GL_STATIC_DRAW);
 
     x, y = 0, 0
     while @window.open?