From dfc6a0cfe88f6e401d21ac6c8a6268c4432dd431 Mon Sep 17 00:00:00 2001
From: Cyberarm <matthewlikesrobots@gmail.com>
Date: Thu, 22 Mar 2018 22:27:56 -0500
Subject: [PATCH] Got basic terrain generation working in immediate mode, all
 list is bugged atm.

---
 lib/objects/terrain.rb | 97 ++++++++++++++++++++++++++++++++++++------
 1 file changed, 85 insertions(+), 12 deletions(-)

diff --git a/lib/objects/terrain.rb b/lib/objects/terrain.rb
index 31aeb86..9415a61 100644
--- a/lib/objects/terrain.rb
+++ b/lib/objects/terrain.rb
@@ -2,28 +2,101 @@ class IMICFPS
   class Terrain
     include OpenGL
     def initialize(size:, heightmap: nil)
-      @size = size.to_f
+      @size = size
       @heightmap = heightmap
+      @map = []
+
+      @vertices = []
+      @normals  = []
+      @colors   = []
+      generate
+    end
+
+    def generate
+      # x
+      @size.times do |x|
+        height = 0
+        # row = []
+        @size.times do |z|
+          @map << Vertex.new(x, height, z)
+          @map << Vertex.new(x, height, z-1)
+          @map << Vertex.new(x+1, height, z-1)
+
+          @map << Vertex.new(x, height, z)
+          @map << Vertex.new(x+1, height, z)
+          @map << Vertex.new(x+1, height, z-1)
+          # height +=0.5
+        end
+
+        # @map << row
+      end
+
+      @map.size do |i|
+        @vertices << @map[i].x
+        @vertices << @map[i].y
+        @vertices << @map[i].z
+        @vertices << 1.0
+        normal = Vertex.new(0,1,0)
+        @normals << normal.x
+        @normals << normal.y
+        @normals << normal.z
+        color = Vertex.new(0,rand(0.2..1.0),0)
+        @colors << color.red
+        @colors << color.green
+        @colors << color.blue
+      end
+      @vertices = @vertices.pack("f*")
+      @normals = @normals.pack("f*")
+      @colors = @colors.pack("f*")
     end
 
     def draw
+      new_draw
+      old_draw
+    end
+
+    def old_draw
       height = 0
       glEnable(GL_COLOR_MATERIAL)
 
-      glBegin(GL_TRIANGLES)
-        glNormal3f(0,1,0)
-        glColor3f(1, 0.5, 0.0)
-        glVertex3f(-@size/2,height,-@size/2)
-        glVertex3f(-@size/2,height,@size/2)
-        glVertex3f(@size/2,height,@size/2)
+      glPolygonMode(GL_FRONT_AND_BACK, GL_LINE)
 
-        glColor3f(0, 0.5, 0.0)
-        glVertex3f(@size/2,height,@size/2)
-        glVertex3f(@size/2,height,-@size/2)
-        glVertex3f(-@size/2,height,-@size/2)
-      glEnd
+          glBegin(GL_TRIANGLES)
+            @map.each do |vertex|
+              glNormal3f(0,1,0)
+              glColor3f(0.0, 0.5, 0)
+              glVertex3f(vertex.x, vertex.y, vertex.z)
+            end
+          glEnd
 
       glDisable(GL_COLOR_MATERIAL)
+      glPolygonMode(GL_FRONT_AND_BACK, GL_FILL)
+    end
+
+    def new_draw
+      glPolygonMode(GL_FRONT_AND_BACK, GL_LINE)
+      glEnable(GL_NORMALIZE)
+      glPushMatrix
+
+      glEnable(GL_COLOR_MATERIAL)
+      glColorMaterial(GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE)
+      glShadeModel(GL_SMOOTH)
+      glEnableClientState(GL_VERTEX_ARRAY)
+      glEnableClientState(GL_NORMAL_ARRAY)
+      glEnableClientState(GL_COLOR_ARRAY)
+
+      glVertexPointer(4, GL_FLOAT, 0, @vertices)
+      glNormalPointer(GL_FLOAT, 0, @normals)
+      glColorPointer(3, GL_FLOAT, 0, @colors)
+
+      glDrawArrays(GL_TRIANGLES, 0, @map.size/4)
+
+      glDisableClientState(GL_VERTEX_ARRAY)
+      glDisableClientState(GL_NORMAL_ARRAY)
+      glDisableClientState(GL_COLOR_ARRAY)
+
+      glPopMatrix
+      glPolygonMode(GL_FRONT_AND_BACK, GL_FILL)
     end
   end
 end