Mali GPU User Interface Engine Application Development Guide

Matrix and Vector Operationsmat4 perspective()matn rotation()Creates a 4x4 perspective transform matrix, constructed from the given field ofview, aspect angle, near plane, and far plane.mat4 perspectiveMatrix = mat4::perspective(45.0f, // field4.0f/3.0f, // aspect1.0f, // near plane1000.0f); // far planeThe perspective matrix is typically used with the camera view to create the worldview:mat4 world = mat4::identity(); // could be a translation or rotationmat4 proj = mat4::perspective(30.0f, 1.0f, 0.1f, 20.0f);mat4 view = mat4::lookAt(camPos, camTarget, upVector);mat4 wvpMatrix = proj * view * world;context->setUniformMatrix("WORLD_VIEW_PROJECTION", wvpMatrix);The vertex shader uses the world view to transform each point:attribute vec4 POSITION; // position of a point on the shapeWORLD_VIEW_PROJECTION; // transformation matrix passedvoid main(void){gl_Position = WORLD_VIEW_PROJECTION * POSITION;}Creates a nxn rotation matrix, calculated based on the passed axis and angleparameters. n is in the range 2 to 4.mat4 matrix = mat4::rotation(45.0, // angle to rotatevec3(1.0f, 0.0f, 0.0f)); // rotation axismatn scale()Creates a nxn scale matrix. n is 3 or 4.mat4 matrix = mat4::scale(2.0f, 2.0f, 2.0f); // x, y, z scale factorsmat4 toMat3()Creates a new matrix from the upper left 3x3 elements of the original matrix.mat4 m1;mat3 m2 = m1.toMat3();mat4 translation()Creates a 4x4 translation matrix. The parameters can be a vector or the x, y, andz translation values:vec3 trans_vec = vec3(2.0f, 3.0f, 4.0f);mat4 matrix = mat4::translation(2.0f, 3.0f, 4.0f);mat4 matrix = mat4::translation(trans_vec);The following vector functions in the MDE library simplify vector operations:vecn crossProduct()vecn length()Returns the cross product of two vectors. For two 3D vectors, the cross productresults in a vector that is perpendicular to both of the original vectors.Returns the length of the vector.vecn scale() Scale the vector by the elements of a vector or by a constant.ARM DUI 0527A-02a Copyright © 2010 ARM. All rights reserved. A-3ID070710Non-Confidential - Draft - Beta