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diff --git a/v_windows/v/vlib/gg/m4/graphic.v b/v_windows/v/vlib/gg/m4/graphic.v
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+++ b/v_windows/v/vlib/gg/m4/graphic.v
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+/**********************************************************************
+*
+* Simply vector/matrix graphic utility
+*
+* Copyright (c) 2021 Dario Deledda. All rights reserved.
+* Use of this source code is governed by an MIT license
+* that can be found in the LICENSE file.
+*
+* TODO:
+**********************************************************************/
+module m4
+
+import math
+
+// Translate degrees to radians
+[inline]
+pub fn rad(deg f32) f32 {
+	return (math.pi / 180.0) * deg
+}
+
+// Translate radians to degrees
+[inline]
+pub fn deg(grad f32) f32 {
+	return (180.0 / math.pi) * grad
+}
+
+// calculate the Orthographic projection matrix
+pub fn ortho(left f32, right f32, bottom f32, top f32, z_near f32, z_far f32) Mat4 {
+	rml := right - left
+	rpl := right + left
+	tmb := top - bottom
+	tpb := top + bottom
+	fmn := z_far - z_near
+	fpn := z_far + z_near
+	if fmn != 0 {
+		return Mat4{ e: [
+				2 / rml, 0      ,       0, -(rpl / rml),
+				0      , 2 / tmb,       0, -(tpb / tmb),
+				0      ,       0, 2 / fmn, -(fpn / fmn),
+				0      ,       0,       0,            1,
+			]!
+		}
+	} 
+	return Mat4{ e: [
+			2 / rml, 0      ,       0, -(rpl / rml),
+			0      , 2 / tmb,       0, -(tpb / tmb),
+			0      ,       0,       0,            0,
+			0      ,       0,       0,            1,
+		]!
+	}
+}
+
+// Calculate the perspective matrix using (fov:fov, ar:aspect_ratio ,n:near_pane, f:far_plane) as parameters
+pub fn perspective(fov f32, ar f32, n f32, f f32) Mat4 {
+	ctan := f32(1.0 / math.tan(fov * (f32(math.pi) / 360.0))) // for the FOV we use 360 instead 180
+	return Mat4{ e: [
+		  ctan / ar, 	  0,		                   0, 							0,
+			0,		     ctan, 	                     0, 							0,
+			0,		        0,		   (n + f) / (n - f), 			     -1.0,
+			0,		        0, (2.0 * n * f) / (n - f), 	            0,
+		]!
+	}
+}
+
+// Calculate the look-at matrix
+pub fn look_at(eye Vec4, center Vec4, up Vec4) Mat4 {
+	f := (center - eye).normalize3()
+	s := (f % up).normalize3()
+	u := (s % f)
+
+	return Mat4{ e: [
+			/* [0][0] */ s.e[0],
+			/* [0][1] */ u.e[0],
+			/* [0][2] */ - f.e[0],
+			/* [0][3] */ 0,
+
+			/* [1][1] */ s.e[1],
+			/* [1][1] */ u.e[1],
+			/* [1][2] */ - f.e[1],
+			/* [1][3] */ 0,
+
+			/* [2][0] */ s.e[2],
+			/* [2][1] */ u.e[2],
+			/* [2][2] */ - f.e[2],
+			/* [2][3] */ 0,
+
+			/* [3][0] */ - (s * eye),
+			/* [3][1] */ - (u * eye),
+			/* [3][2] */ f * eye,
+			/* [3][3] */ 1,
+		]!
+	}
+}
+
+
+// Get the complete transformation matrix for GLSL demos
+pub fn calc_tr_matrices(w f32, h f32, rx f32, ry f32, in_scale f32) Mat4 {
+	proj := perspective(60, w / h, 0.01, 10.0)
+	view := look_at(Vec4{ e: [f32(0.0), 1.5, 6, 0]! }, Vec4{ e: [f32(0), 0, 0, 0]! }, Vec4{ e: [f32(0), 1.0, 0, 0]! })
+	view_proj := view * proj
+
+	rxm := rotate(rad(rx), Vec4{ e: [f32(1), 0, 0, 0]! })
+	rym := rotate(rad(ry), Vec4{ e: [f32(0), 1, 0, 0]! })
+
+	model := rym * rxm
+	scale_m := scale(Vec4{ e: [in_scale, in_scale, in_scale, 1]! })
+
+	res := (scale_m * model) * view_proj
+	return res
+}