More code restructuring and system access functions.

system_util.go

@@ -0,0 +1,51 @@
+package goga
+
+func GetSpriteRenderer() *SpriteRenderer {
+	renderer, ok := GetSystemByName(sprite_renderer_name).(*SpriteRenderer)
+
+	if !ok {
+		panic("Could not obtain sprite renderer")
+	}
+
+	return renderer
+}
+
+func GetModelRenderer() *ModelRenderer {
+	renderer, ok := GetSystemByName(model_renderer_name).(*ModelRenderer)
+
+	if !ok {
+		panic("Could not obtain model renderer")
+	}
+
+	return renderer
+}
+
+func GetCulling2DSystem() *Culling2D {
+	system, ok := GetSystemByName(culling_2d_name).(*Culling2D)
+
+	if !ok {
+		panic("Could not obtain culling system")
+	}
+
+	return system
+}
+
+func GetKeyframeRenderer() *KeyframeRenderer {
+	renderer, ok := GetSystemByName(keyframe_sprite_renderer_name).(*KeyframeRenderer)
+
+	if !ok {
+		panic("Could not obtain keyframe renderer")
+	}
+
+	return renderer
+}
+
+func GetTextRenderer() *TextRenderer {
+	renderer, ok := GetSystemByName(text_renderer_name).(*TextRenderer)
+
+	if !ok {
+		panic("Could not obtain text renderer")
+	}
+
+	return renderer
+}