add support for skeletal animation

Sandbox/assets/shaders/Grid.glsl

@@ -0,0 +1,50 @@
+// Simple Texture Shader
+
+#type vertex
+#version 430
+
+layout(location = 0) in vec3 a_Position;
+layout(location = 4) in vec2 a_TexCoord;
+
+uniform mat4 u_MVP;
+
+out vec2 v_TexCoord;
+
+void main()
+{
+    vec4 position = u_MVP * vec4(a_Position, 1.0);
+    gl_Position = position;
+
+    v_TexCoord = a_TexCoord;
+}
+
+#type fragment
+#version 430
+
+layout(location = 0) out vec4 color;
+
+uniform sampler2D u_Texture;
+uniform float u_Scale;
+uniform float u_Res;
+
+in vec2 v_TexCoord;
+
+/*void main()
+{
+	color = texture(u_Texture, v_TexCoord * 8.0);
+}*/
+
+float grid(vec2 st, float res)
+{
+    vec2 grid = fract(st);
+    return step(res, grid.x) * step(res, grid.y);
+}
+
+void main()
+{
+    float scale = u_Scale;
+    float resolution = u_Res;
+
+    float x = grid(v_TexCoord * scale, resolution);
+    color = vec4(vec3(0.2), 0.5) * (1.0 - x);
+}