setOrthographicMatrix function
void
setOrthographicMatrix()
Constructs an OpenGL orthographic projection matrix in orthographicMatrix.
left, right specify the coordinates for the left and right vertical
clipping planes.
bottom, top specify the coordinates for the bottom and top horizontal
clipping planes.
near, far specify the coordinates to the near and far depth clipping
planes.
Implementation
void setOrthographicMatrix(Matrix4 orthographicMatrix, double left,
double right, double bottom, double top, double near, double far) {
final rml = right - left;
final rpl = right + left;
final tmb = top - bottom;
final tpb = top + bottom;
final fmn = far - near;
final fpn = far + near;
orthographicMatrix
..setZero()
..setEntry(0, 0, 2.0 / rml)
..setEntry(1, 1, 2.0 / tmb)
..setEntry(2, 2, -2.0 / fmn)
..setEntry(0, 3, -rpl / rml)
..setEntry(1, 3, -tpb / tmb)
..setEntry(2, 3, -fpn / fmn)
..setEntry(3, 3, 1.0);
}