From: Alexis Laferrière <alexis.laf@xymus.net>
Date: Wed, 10 Feb 2016 02:37:56 +0000 (-0500)
Subject: lib/gamnit: intro draw_mode
X-Git-Url: http://nitlanguage.org

lib/gamnit: intro draw_mode

This is very useful to create optimized Mesh, using gl_TRIANGLE_STRIP and gl_TRIANGLE_FAN.

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>
---

diff --git a/lib/gamnit/depth/depth_core.nit b/lib/gamnit/depth/depth_core.nit
index 03a3970..f1e5803 100644
--- a/lib/gamnit/depth/depth_core.nit
+++ b/lib/gamnit/depth/depth_core.nit
@@ -103,6 +103,9 @@ class Mesh
 	# Coordinates on the texture per vertex
 	var texture_coords = new Array[Float] is lazy, writable
 
+	# `GLDrawMode` used to display this mesh, defaults to `gl_TRIANGLES`
+	fun draw_mode: GLDrawMode do return gl_TRIANGLES
+
 	# Create an UV sphere of `radius` with `n_meridians` and `n_parallels`
 	init uv_sphere(radius: Float, n_meridians, n_parallels: Int)
 	do
diff --git a/lib/gamnit/depth/more_materials.nit b/lib/gamnit/depth/more_materials.nit
index 6117128..b77c85e 100644
--- a/lib/gamnit/depth/more_materials.nit
+++ b/lib/gamnit/depth/more_materials.nit
@@ -75,9 +75,9 @@ class SmoothMaterial
 
 		# Execute draw
 		if mesh.indices.is_empty then
-			glDrawArrays(gl_TRIANGLES, 0, mesh.vertices.length/3)
+			glDrawArrays(mesh.draw_mode, 0, mesh.vertices.length/3)
 		else
-			glDrawElements(gl_TRIANGLES, mesh.indices.length, gl_UNSIGNED_SHORT, mesh.indices_c.native_array)
+			glDrawElements(mesh.draw_mode, mesh.indices.length, gl_UNSIGNED_SHORT, mesh.indices_c.native_array)
 		end
 	end
 end
@@ -182,9 +182,9 @@ class TexturedMaterial
 		program.camera.uniform(app.world_camera.position.x, app.world_camera.position.y, app.world_camera.position.z)
 
 		if mesh.indices.is_empty then
-			glDrawArrays(gl_TRIANGLES, 0, mesh.vertices.length/3)
+			glDrawArrays(mesh.draw_mode, 0, mesh.vertices.length/3)
 		else
-			glDrawElements(gl_TRIANGLES, mesh.indices.length, gl_UNSIGNED_SHORT, mesh.indices_c.native_array)
+			glDrawElements(mesh.draw_mode, mesh.indices.length, gl_UNSIGNED_SHORT, mesh.indices_c.native_array)
 		end
 	end
 end
@@ -220,9 +220,9 @@ class NormalsMaterial
 		program.normal.array(mesh.normals, 3)
 
 		if mesh.indices.is_empty then
-			glDrawArrays(gl_TRIANGLES, 0, mesh.vertices.length/3)
+			glDrawArrays(mesh.draw_mode, 0, mesh.vertices.length/3)
 		else
-			glDrawElements(gl_TRIANGLES, mesh.indices.length, gl_UNSIGNED_SHORT, mesh.indices_c.native_array)
+			glDrawElements(mesh.draw_mode, mesh.indices.length, gl_UNSIGNED_SHORT, mesh.indices_c.native_array)
 		end
 	end
 end