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diff --git a/src/ru/olamedia/camera/CameraProjectionMatrix.java b/src/ru/olamedia/camera/CameraProjectionMatrix.java
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+++ b/src/ru/olamedia/camera/CameraProjectionMatrix.java
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+package ru.olamedia.camera;
+
+import org.openmali.FastMath;
+import org.openmali.vecmath2.Matrix4f;
+
+public class CameraProjectionMatrix extends Matrix4f {
+
+	/**
+	 * Creates a mesa-style perspective projection transform, that mimics a
+	 * standard, camera-based, view-model.
+	 * 
+	 * @param fovy
+	 *            specifies the field of view in the y direction, in radians
+	 * @param aspect
+	 *            specifies the aspect ratio and thus the field of view in the x
+	 *            direction. The aspect ratio is the ratio of x to y, or width
+	 *            to height.
+	 * @param zNear
+	 *            the distance to the frustum's near clipping plane. This value
+	 *            must be positive, (the value -zNear is the location of the
+	 *            near clip plane).
+	 * @param zFar
+	 *            the distance to the frustum's far clipping plane.
+	 */
+	public final void perspectiveMesa(float fovy, float aspect, float zNear,
+			float zFar) {
+		final float ymax = zNear * FastMath.tan(fovy);
+		final float ymin = -ymax;
+		final float xmin = ymin * aspect;
+		final float xmax = ymax * aspect;
+
+		// don't call glFrustum() because of error semantics (covglu)
+		frustumMesa(xmin, xmax, ymin, ymax, zNear, zFar);
+	}
+
+	/**
+	 * Creates a masa-style perspective projection transform, that mimics a
+	 * standard, camera-based, view-model. The frustum function-call establishes
+	 * a view-model with the eye at the apex of a symmetric view frustum. The
+	 * arguments define the frustum and its associated perspective projection:
+	 * (left, bottom, -near) and (right, top, -near) specify the point on the
+	 * near clipping plane that maps onto the lower-left and upper-right corners
+	 * of the window respectively, assuming the eye is located at (0, 0, 0).
+	 * 
+	 * @param left
+	 *            the vertical line on the left edge of the near clipping plane
+	 *            mapped to the left edge of the graphics window
+	 * @param right
+	 *            the vertical line on the right edge of the near clipping plane
+	 *            mapped to the right edge of the graphics window
+	 * @param bottom
+	 *            the horizontal line on the bottom edge of the near clipping
+	 *            plane mapped to the bottom edge of the graphics window
+	 * @param top
+	 *            the horizontal line on the top edge of the near
+	 * @param zNear
+	 *            the distance to the frustum's near clipping plane. This value
+	 *            must be positive, (the value -near is the location of the near
+	 *            clip plane).
+	 * @param zFar
+	 *            the distance to the frustum's far clipping plane. This value
+	 *            must be positive, and must be greater than near.
+	 */
+	public final void frustumMesa(float left, float right, float bottom,
+			float top, float zNear, float zFar) {
+		final float x = (2.0f * zNear) / (right - left);
+		final float y = (2.0f * zNear) / (top - bottom);
+		final float a = (right + left) / (right - left);
+		final float b = (top + bottom) / (top - bottom);
+		final float c = -(zFar + zNear) / (zFar - zNear);
+		final float d = -(2.0f * zFar * zNear) / (zFar - zNear);
+
+		this.set(x, 0f, 0f, 0f, 0f, y, 0f, 0f, a, b, c, -1f, 0f, 0f, d, 0f);
+
+	}
+
+}