GLLib: GLLib : Math Utils

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GLLib : Math Utils
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mathematic function More...

Functions

static String ConvertFixedPointToString (int value, int precision)
 Converts a GLLib Fixed Point number to a string in base 10.
static final long Math_Abs (long a)
static final int Math_Abs (int a)
static int Math_Atan (int dx, int dy)
 Arctangent.
static int Math_AtanSlow (int dx, int dy)
 Arctangent, very slow but accurate method, it find angle by dichotomy.
static void Math_Bezier2D (int x1, int y1, int x2, int y2, int x3, int y3, int interp)
 Three control point 2D Bezier interpolation.
static void Math_Bezier3D (int x1, int y1, int z1, int x2, int y2, int z2, int x3, int y3, int z3, int interp)
 Three control point 3D Bezier interpolation.
static int Math_Cos (int angle)
 Cosinus.
static int Math_DegreeToFixedPointAngle (int a)
 Convert a degree angle into a fixed point angle.
static int Math_Det (int x1, int y1, int x2, int y2)
 Compute the determinant of 2 2Dvector.
static int Math_DistPointLine (int x0, int y0, int x1, int y1, int x2, int y2) throws Exception
 Compute the distance from a point to a segment/line.
static int Math_Div10 (int a)
 Divide by 10 a number, with result in fixed point.
static int Math_DotProduct (int x1, int y1, int x2, int y2)
 Compute the dot product of 2 2Dvector.
static int Math_FixedPoint_Add (int summand1, int summand2)
 Addition for Fixed Point.
static int Math_FixedPoint_DegreesToAngleFixedPoint (int angle)
 Convert an angle from degrees to fixed point angle.
static int Math_FixedPoint_DegreesToRadians (int angle)
 Convert an angle from degrees to radians (both fixed point and not, since this is just a ratio).
static int Math_FixedPoint_Det (int x1, int y1, int x2, int y2)
 Compute the determinant of 2 2Dvector in Fixed Point.
static int Math_FixedPoint_Divide (int dividend, int divisor)
 Division for Fixed Point.
static int Math_FixedPoint_DotProduct (int x1, int y1, int x2, int y2)
 Compute the dot product of 2 2Dvector in Fixed Point.
static int Math_FixedPoint_LineCircleIntersect (int in_x1, int in_y1, int in_x2, int in_y2, int in_circleX, int in_circleY, int in_radius)
 Find intersect points between a line and a circle.
static int Math_FixedPoint_LineRectangleIntersect (int in_x1, int in_y1, int in_x2, int in_y2, int in_rectX, int in_rectY, int in_rectW, int in_rectH)
 Find intersect points between a line and a rectangle.
static int Math_FixedPoint_Multiply (int multiplicand, int multiplier)
 Multiplication for Fixed Point.
static int Math_FixedPoint_Norm (int x, int y)
 Nnormal of a vector in Fixed Point.
static int Math_FixedPoint_NormPow (int x, int y)
 Compute pow of the normal of a vector in Fixed Point.
static int Math_FixedPoint_PointLineDistance (int in_lineX1, int in_lineY1, int in_lineX2, int in_lineY2, int in_pointX, int in_pointY)
 Compute the distance from a point to a segment/line.
static int Math_FixedPoint_RadiansToAngleFixedPoint (int angle)
 Convert an angle from radians to fixed point angle.
static int Math_FixedPoint_RadiansToDegrees (int angle)
 Convert an angle from radians to degrees (both fixed point and not, since this is just a ratio).
static int Math_FixedPoint_Round (int value)
 Rounds value to closest whole number in Fixed Point.
static int Math_FixedPoint_Sqrt (long value)
 Square Root for Long Fixed Point values.
static int Math_FixedPoint_Sqrt (int value)
 Square Root for Integer Fixed Point values.
static int Math_FixedPoint_Square (int value)
 Square for Fixed Point.
static int Math_FixedPoint_Subtract (int minuend, int subtrahend)
 Subtraction for Fixed Point.
static int Math_FixedPointAdjust (int a)
 Adjust a fixed point in base 8 to this fixed point base.
static int Math_FixedPointAngleToDegree (int a)
 Convert a fixed point angle into a degree angle.
static int Math_FixedPointToInt (int a)
 Convert a fixed point value to an int value.
static void Math_Init (String packName, int cos, int sqrt) throws Exception
 Math initialisation, by reading specified table from a package.
static int Math_IntToFixedPoint (int a)
 Convert a fixed point value to an int value.
static int Math_Log2 (int a)
 return log base 2
static final long Math_Max (long a, long b)
static final int Math_Max (int a, int b)
static final long Math_Min (long a, long b)
static final int Math_Min (int a, int b)
static int Math_Norm (int x, int y, int iter)
 Norm following newton law approximation.
static int Math_NormPow (int x1, int y1)
 Compute pow of the normal of a vector.
static void Math_QuickSort (int array[])
 Quicksort an array of integer.
static int[] Math_QuickSortIndices (int data[], int nbItemPerValue, int itemNb)
 Get an array of indice corresponding to the sorting of an array of data.
static int[] Math_QuickSortIndices (int data[])
 Get an array of indice corresponding to the sorting of an array of data.
static void Math_Quit ()
 Free all math arrays.
static final int Math_Rand ()
 Create a random number.
static int Math_Rand (int a, int b)
 Create a random int inside the interval [a, b[.
static final void Math_RandSetSeed (long seed)
 set math random seed
static boolean Math_RectIntersect (int Ax0, int Ay0, int Ax1, int Ay1, int Bx0, int By0, int Bx1, int By1)
 Tell if 2 axis aligned rectangle intersect.
static boolean Math_SameSign (int a, int b)
 Test 2 numbers to see if they are both of the same sign.
static int Math_SegmentIntersect (int x1, int y1, int x2, int y2, int x3, int y3, int x4, int y4)
 Tell if 2 segment intersect themselves.
static int Math_Sin (int a)
 Sinus.
static int Math_Sqrt (long val)
 Square Root slow.
static int Math_Sqrt (int x)
 Square Root.
static int Math_Sqrt_FixedPoint (int val, int precisionLoop)
 Square Root for Fixed Point.
static int Math_Tan (int angle)
 Tangent.

Variables

static final int Math_Angle180 = Math_DegreeToFixedPointAngle(180)
 180 in fixed point
static final int Math_Angle270 = Math_DegreeToFixedPointAngle(270)
 270 in fixed point
static final int Math_Angle360 = Math_DegreeToFixedPointAngle(360)
 360 in fixed point
static final int Math_Angle90 = Math_DegreeToFixedPointAngle(90)
 90 in fixed point
static final int Math_AngleMUL = 1 << GLLibConfig.math_angleFixedPointBase
 angle fixed point multiplier eg one degree in fixed point base.(not equal to Math_DegreeToFixedPointAngle(1))
static final int Math_FixedPoint_E = 1459366444 >> (29 - GLLibConfig.math_fixedPointBase)
static final int Math_FixedPoint_PI = 1686629713 >> (29 - GLLibConfig.math_fixedPointBase)
static final int MATH_INTERSECT_NO_INTERSECT = 0
static final int MATH_INTERSECT_ONE_POINT = (1 << 1)
static final int MATH_INTERSECT_TWO_POINTS = (1 << 2)
static final int MATH_SEGMENTINTERSECT_COLLINEAR = -1
 return value of Math_segmentIntersect if there is no or full intersection because both segment are colinear
static final int MATH_SEGMENTINTERSECT_DO_INTERSECT = 1
 return value of Math_segmentIntersect if there is an intersection
static final int MATH_SEGMENTINTERSECT_DONT_INTERSECT = 0
 return value of Math_segmentIntersect if there is no intersection
static int s_math_bezierX
 x coordinate of bezier interpolated value through Math_Bezier2D or Math_Bezier3D
static int s_math_bezierY
 y coordinate of bezier interpolated value through Math_Bezier2D or Math_Bezier3D
static int s_math_bezierZ
 z coordinate of bezier interpolated value through Math_Bezier3D
static int s_Math_distPointLineX
 x coordinate of orthogonal projection of point on a segment using Math_distPointLine
static int s_Math_distPointLineY
 y coordinate of orthogonal projection of point on a segment using Math_distPointLine
static final int s_math_F_05 = (s_math_F_1>>1)
 Fixed point value for number 0.5.
static final int s_math_F_1 = 1 << GLLibConfig.math_fixedPointBase
 Fixed point value for number 1.
static int s_Math_intersectPoints [][] = new int[2][2]
static int s_Math_intersectX
 x coordinate of intersection point of 2 segment using Math_segmentIntersect
static int s_Math_intersectY
 y coordinate of intersection point of 2 segment using Math_segmentIntersect
static java.util.Random s_math_random
 Random number generator.

Detailed Description

mathematic function

Function Documentation

static String ConvertFixedPointToString ( int  value,
int  precision 
) [static, package, inherited]

Converts a GLLib Fixed Point number to a string in base 10.

Parameters:
value Fixed Point value to be converted.
precision Number or of decimals to print.
Returns:
String representaion of Fixed Point number in base 10

static final long Math_Abs ( long  a  )  [static, package, inherited]

static final int Math_Abs ( int  a  )  [static, package, inherited]

static int Math_Atan ( int  dx,
int  dy 
) [static, package, inherited]

Arctangent.

Note:
this function will create a cache to speed up calculation if GLLibConfig.math_AtanUseCacheTable is set to true, but will also consume up to ((1<<math_fixedPointBase)+1)*4 byte
Parameters:
dx,dy Slope of the angle.
Returns:
Arctangent of the slope.
Note:
This is not the real atan func as found in common device, it will return an angle in [0, 1] and not in [0, PI/2].

static int Math_AtanSlow ( int  dx,
int  dy 
) [static, package, inherited]

Arctangent, very slow but accurate method, it find angle by dichotomy.

Parameters:
dx,dy Slope of the angle.
Returns:
Arctangent of the slope.
Note:
This is not the real atan func as found in common device, it will return an angle in [0, 1] and not in [0, PI/2].

static void Math_Bezier2D ( int  x1,
int  y1,
int  x2,
int  y2,
int  x3,
int  y3,
int  interp 
) [static, package, inherited]

Three control point 2D Bezier interpolation.

Parameters:
x1,y1 First control point.
x2,y2 Second control point.
x3,y3 Third control point.
interp Interpolation value (ranges from 0 to s_math_F_1).
Returns:
Result returned in s_math_bezierX, s_math_bezierY.

static void Math_Bezier3D ( int  x1,
int  y1,
int  z1,
int  x2,
int  y2,
int  z2,
int  x3,
int  y3,
int  z3,
int  interp 
) [static, package, inherited]

Three control point 3D Bezier interpolation.

Parameters:
x1,y1,z1 First control point.
x2,y2,z2 Second control point.
x3,y3,z3 Third control point.
interp Interpolation value (ranges from 0 to s_math_F_1).
Returns:
Result returned in s_math_bezierX, s_math_bezierY, s_math_bezierZ.

static int Math_Cos ( int  angle  )  [static, package, inherited]

Cosinus.

Parameters:
angle - angle in fixed point 0=0 (1<<math_angleFixedPointBase)=360.
Returns:
Cosinus value of the angle in fixed Point

static int Math_DegreeToFixedPointAngle ( int  a  )  [static, package, inherited]

Convert a degree angle into a fixed point angle.

Parameters:
an angle in degrees.
Returns:
angle in fixed point.

static int Math_Det ( int  x1,
int  y1,
int  x2,
int  y2 
) [static, package, inherited]

Compute the determinant of 2 2Dvector.

Parameters:
x1,y1 X & Y value of the first vector.
x2,y2 X & Y value of the second vector.
Returns:
The determinant of the 2 vectors.

static int Math_DistPointLine ( int  x0,
int  y0,
int  x1,
int  y1,
int  x2,
int  y2 
) throws Exception [static, package, inherited]

Compute the distance from a point to a segment/line.

Calculate coordinate of orthogonal projection of point on segment as well.

Parameters:
(x0,y0)(x1,y1) Coordinate of segment.
(x2,y2) Coordinate of point.
Returns:
Distance from point to segment (orthogonal projection) in fixed point.
Note:
Coordinates of projected point are saved in (s_Math_distPointLineX, s_Math_distPointLineY).

static int Math_Div10 ( int  a  )  [static, package, inherited]

Divide by 10 a number, with result in fixed point.

Faster than classical division.

Parameters:
a Number to divide by 10.
Returns:
Fixed point value of the number divided by 10.

static int Math_DotProduct ( int  x1,
int  y1,
int  x2,
int  y2 
) [static, package, inherited]

Compute the dot product of 2 2Dvector.

Parameters:
x1,y1 X & Y value of the first vector.
x2,y2 X & Y value of the second vector.
Returns:
The dot product of the 2 vectors.

static int Math_FixedPoint_Add ( int  summand1,
int  summand2 
) [static, package, inherited]

Addition for Fixed Point.

Parameters:
summand1 Number to be added in Fixed Point.
summand2 Number to be added in Fixed Point.
Returns:
Sum of summand1 and summand2 in Fixed Point.
Note:
An assert will indicate if the result overflows Integer.MAX_VALUE.

static int Math_FixedPoint_DegreesToAngleFixedPoint ( int  angle  )  [static, package, inherited]

Convert an angle from degrees to fixed point angle.

Parameters:
angle in degrees to be converted.
Returns:
angle in Fixed Point.

static int Math_FixedPoint_DegreesToRadians ( int  angle  )  [static, package, inherited]

Convert an angle from degrees to radians (both fixed point and not, since this is just a ratio).

Parameters:
angle in degrees to be converted into radians.
Returns:
angle in radians. (same precision as input param)

static int Math_FixedPoint_Det ( int  x1,
int  y1,
int  x2,
int  y2 
) [static, package, inherited]

Compute the determinant of 2 2Dvector in Fixed Point.

Parameters:
x1,y1 X & Y value of the first vector in Fixed Point.
x2,y2 X & Y value of the second vector in Fixed Point.
Returns:
The determinant of the 2 vectors in Fixed Point.

static int Math_FixedPoint_Divide ( int  dividend,
int  divisor 
) [static, package, inherited]

Division for Fixed Point.

Parameters:
dividend Number to be divided in Fixed Point.
divisor Number to be divided by in Fixed Point.
Returns:
Quotient of dividend and divisor in Fixed Point.
Note:
An assert will indicate a division by zero.

static int Math_FixedPoint_DotProduct ( int  x1,
int  y1,
int  x2,
int  y2 
) [static, package, inherited]

Compute the dot product of 2 2Dvector in Fixed Point.

Parameters:
x1,y1 X & Y value of the first vector in Fixed Point.
x2,y2 X & Y value of the second vector in Fixed Point.
Returns:
The dot product of the 2 vectors in Fixed Point.

static int Math_FixedPoint_LineCircleIntersect ( int  in_x1,
int  in_y1,
int  in_x2,
int  in_y2,
int  in_circleX,
int  in_circleY,
int  in_radius 
) [static, package, inherited]

Find intersect points between a line and a circle.

Parameters:
(in_x1,in_y1) first point on the line.
(in_x2,in_y2) second point on the line.
(in_circleX,in_circleY) center coordinates of circle.
(in_radius) radius of the circle.
Returns:
MATH_INTERSECT_NO_INTERSECT if no intersect between line and circle. MATH_INTERSECT_ONE_POINT if only one intersect point between line and circle (Tangeant). MATH_INTERSECT_TWO_POINTS if two intersect ponts between line and circle.
Note:
Coordinates of intersection points are saved in the array s_Math_intersectPoints[][] First index indicates point: 0 = first point and 1 = second point Second index indicates x or y coordinate: 0 = x coordinate and 1 = y coordinate

static int Math_FixedPoint_LineRectangleIntersect ( int  in_x1,
int  in_y1,
int  in_x2,
int  in_y2,
int  in_rectX,
int  in_rectY,
int  in_rectW,
int  in_rectH 
) [static, package, inherited]

Find intersect points between a line and a rectangle.

Parameters:
(in_x1,in_y1) first point on the line.
(in_x2,in_y2) second point on the line.
(in_rectX,in_rectY) coordinates of top-left corner of rectangle.
(in_rectW,in_rectH) Width and Height of rectangle.
Returns:
MATH_INTERSECT_NO_INTERSECT if no intersect between line and rectangle. MATH_INTERSECT_ONE_POINT if only one intersect point between line and rectangle . MATH_INTERSECT_TWO_POINTS if two intersect points between line and circle.
Note:
Coordinates of intersection points are saved in the array s_Math_intersectPoints[][] First index indicates point: 0 = first point and 1 = second point Second index indicates x or y coordinate: 0 = x coordinate and 1 = y coordinate

static int Math_FixedPoint_Multiply ( int  multiplicand,
int  multiplier 
) [static, package, inherited]

Multiplication for Fixed Point.

Parameters:
multiplicand Number to be mutiplied in Fixed Point.
multiplier Number to be multiplied by in Fixed Point.
Returns:
Product of multiplicand and multiplier in Fixed Point.
Note:
An assert will indicate if the result overflows Integer.MAX_VALUE.

static int Math_FixedPoint_Norm ( int  x,
int  y 
) [static, package, inherited]

Nnormal of a vector in Fixed Point.

Parameters:
x,y X & Y value of the vector in Fixed Point.
Returns:
norm of vector (x,y).

static int Math_FixedPoint_NormPow ( int  x,
int  y 
) [static, package, inherited]

Compute pow of the normal of a vector in Fixed Point.

Parameters:
x,y X & Y value of the vector in Fixed Point.
Returns:
The pow of the normal of the vector in Fixed Point.
Note:
An assert will indicate if the result overflows Integer.MAX_VALUE.

static int Math_FixedPoint_PointLineDistance ( int  in_lineX1,
int  in_lineY1,
int  in_lineX2,
int  in_lineY2,
int  in_pointX,
int  in_pointY 
) [static, package, inherited]

Compute the distance from a point to a segment/line.

Calculate coordinate of orthogonal projection of point on segment as well.

Parameters:
(in_lineX1,in_lineY1)(in_lineX2,in_lineY2) Coordinate of segment.
(in_pointX,in_pointY) Coordinate of point.
Returns:
Distance from point to segment (orthogonal projection) in fixed point.
Note:
Coordinates of intersection points in fixed Point are saved in (s_Math_distPointLineX, s_Math_distPointLineY).

static int Math_FixedPoint_RadiansToAngleFixedPoint ( int  angle  )  [static, package, inherited]

Convert an angle from radians to fixed point angle.

Parameters:
angle in radians to be converted.
Returns:
angle in Fixed Point.

static int Math_FixedPoint_RadiansToDegrees ( int  angle  )  [static, package, inherited]

Convert an angle from radians to degrees (both fixed point and not, since this is just a ratio).

Parameters:
angle in radians to be converted into degrees.
Returns:
angle in degress. (same precision as input param)

static int Math_FixedPoint_Round ( int  value  )  [static, package, inherited]

Rounds value to closest whole number in Fixed Point.

Parameters:
value Value to be rounded in Fixed Point.
Returns:
Rounded value in Fixed Point.

static int Math_FixedPoint_Sqrt ( long  value  )  [static, package, inherited]

Square Root for Long Fixed Point values.

Parameters:
value Number to get square root of.
Returns:
Square root of val in Fixed Point.
Note:
Iterative process, precise but can be slow, use with caution.

static int Math_FixedPoint_Sqrt ( int  value  )  [static, package, inherited]

Square Root for Integer Fixed Point values.

Parameters:
value Number to get square root of.
Returns:
Square root of val in Fixed Point.
Note:
Iterative process, precise but can be slow, use with caution.

static int Math_FixedPoint_Square ( int  value  )  [static, package, inherited]

Square for Fixed Point.

Parameters:
value Number to be squared in Fixed Point.
Returns:
Squared value in Fixed Point.

static int Math_FixedPoint_Subtract ( int  minuend,
int  subtrahend 
) [static, package, inherited]

Subtraction for Fixed Point.

Parameters:
minuend Number to be subtracted from in Fixed Point.
subtrahend Number to be subtracted in Fixed Point.
Returns:
Difference of minuend and subtrahend in Fixed Point.
Note:
An assert will indicate if the result overflows Integer.MAX_VALUE.

static int Math_FixedPointAdjust ( int  a  )  [static, package, inherited]

Adjust a fixed point in base 8 to this fixed point base.

Parameters:
a Value to adjsut.
Returns:
The value ajusted.

static int Math_FixedPointAngleToDegree ( int  a  )  [static, package, inherited]

Convert a fixed point angle into a degree angle.

Parameters:
an angle in fixed point.
Returns:
angle in degrees.

static int Math_FixedPointToInt ( int  a  )  [static, package, inherited]

Convert a fixed point value to an int value.

Parameters:
a Fixed point value to convert to int.
Returns:
Int value of a.

static void Math_Init ( String  packName,
int  cos,
int  sqrt 
) throws Exception [static, package, inherited]

Math initialisation, by reading specified table from a package.

Parameters:
packName Name of the pack witch contains math table.
cos Index of cosine table in the pack. Use -1 if no table but all call to Math_Cos & Math_Sin will fail.
sqrt Index of sqrt table in the pack. Use -1 if no table but all call to Math_sqrt will fail.
Returns:
True if everything was loaded as requested.

static int Math_IntToFixedPoint ( int  a  )  [static, package, inherited]

Convert a fixed point value to an int value.

Parameters:
a Value to convert to fixed point.
Returns:
Fixed point value of a.

static int Math_Log2 ( int  a  )  [static, package, inherited]

return log base 2

Parameters:
a value to calculate log base 2
Returns:
log base 2 of value

static final long Math_Max ( long  a,
long  b 
) [static, package, inherited]

static final int Math_Max ( int  a,
int  b 
) [static, package, inherited]

static final long Math_Min ( long  a,
long  b 
) [static, package, inherited]

static final int Math_Min ( int  a,
int  b 
) [static, package, inherited]

static int Math_Norm ( int  x,
int  y,
int  iter 
) [static, package, inherited]

Norm following newton law approximation.

Sqrt(n) is provided by iteration of xk = (xk + n / xk) / 2. The more iteration (k++), the better is the approximation.

Parameters:
x,y X and Y coordinate of vector to get the norm from.
iter Number of iteration to perform, more iteration gives a better result however more iteration are more cpu intensive.
Returns:
norm of vector (x,y).

static int Math_NormPow ( int  x1,
int  y1 
) [static, package, inherited]

Compute pow of the normal of a vector.

Parameters:
x1,y1 X & Y value of the vector.
Returns:
The pow of the normal of the vector.

static void Math_QuickSort ( int  array[]  )  [static, package, inherited]

Quicksort an array of integer.

Parameters:
array Array of data to sort.

static int [] Math_QuickSortIndices ( int  data[],
int  nbItemPerValue,
int  itemNb 
) [static, package, inherited]

Get an array of indice corresponding to the sorting of an array of data.

Example: data={12, 3, 8} return {1, 2, 0} so that data[1] <= data[2] <= data[0].

Parameters:
data Array of data to scale.
nbItemPerValue If data is an array of values, how many item are needed per value.
itemNb If data is an array of values, which item shoudl be considered for sorting.
Returns:
Array of indices, so that data[indices] are sorted.

static int [] Math_QuickSortIndices ( int  data[]  )  [static, package, inherited]

Get an array of indice corresponding to the sorting of an array of data.

Example: data={12, 3, 8} return {1, 2, 0} so that data[1] <= data[2] <= data[0].

Parameters:
data Array of data to scale.
Returns:
Array of indices, so that data[indices] are sorted.

static void Math_Quit (  )  [static, package, inherited]

Free all math arrays.

static final int Math_Rand (  )  [static, package, inherited]

Create a random number.

Returns:
a random int.

static int Math_Rand ( int  a,
int  b 
) [static, package, inherited]

Create a random int inside the interval [a, b[.

Parameters:
a,b Interval for the random number to generate.
Returns:
A number between [a, b[.
Note:
if a=b then return value is a (or b)

static final void Math_RandSetSeed ( long  seed  )  [static, package, inherited]

set math random seed

Parameters:
seed seed to use for random number generator.

static boolean Math_RectIntersect ( int  Ax0,
int  Ay0,
int  Ax1,
int  Ay1,
int  Bx0,
int  By0,
int  Bx1,
int  By1 
) [static, package, inherited]

Tell if 2 axis aligned rectangle intersect.

Parameters:
(Ax0,Ay0)(Ax1,Ay1) top left and bottom right coordinate of first rectangle
(Bx0,By0)(Bx1,By1) top left and bottom right coordinate of second rectangle
Returns:
true if intersect, false if not

static boolean Math_SameSign ( int  a,
int  b 
) [static, package, inherited]

Test 2 numbers to see if they are both of the same sign.

Parameters:
a,b Numbers to compare.
Returns:
True if both numbers are positive.

True if both numbers are negative.

False Otherwise.

static int Math_SegmentIntersect ( int  x1,
int  y1,
int  x2,
int  y2,
int  x3,
int  y3,
int  x4,
int  y4 
) [static, package, inherited]

Tell if 2 segment intersect themselves.

Parameters:
(x1,y1)(x2,y2) Coordinate of first segment.
(x3,y3)(x4,y4) Coordinate of second segment.
Returns:
  • MATH_SEGMENTINTERSECT_DO_INTERSECT if intersect.
  • MATH_SEGMENTINTERSECT_DONT_INTERSECT if no intersection.
  • MATH_SEGMENTINTERSECT_COLLINEAR if two segment are colinear (full or no intersection).
Note:
Coordinates of intersection point are saved in (s_Math_intersectX, s_Math_intersectY).
Warning:
This function can generate some Overflows if large value are used. Be carefull when using this code with FixedPoint values, the boundaries can change with the value of GLLibConfig.math_fixedPointBase.

static int Math_Sin ( int  a  )  [static, package, inherited]

Sinus.

Parameters:
a Angle in fixed point 0=0 (1<<math_angleFixedPointBase)=360.
Returns:
Sinus value of the angle.

static int Math_Sqrt ( long  val  )  [static, package, inherited]

Square Root slow.

Parameters:
val Number to get square root of.
Returns:
Square root of val.
Note:
long version is way slower than int function

static int Math_Sqrt ( int  x  )  [static, package, inherited]

Square Root.

Parameters:
x Number to get square root of.
Returns:
Square root of x.
Note:
Integer Square Root function. Contributors include Arne Steinarson for the basic approximation idea, Dann Corbit and Mathew Hendry for the first cut at the algorithm, Lawrence Kirby for the rearrangement, improvments and range optimization, Paul Hsieh for the round-then-adjust idea, and Tim Tyler, for the Java port.

static int Math_Sqrt_FixedPoint ( int  val,
int  precisionLoop 
) [static, package, inherited]

Square Root for Fixed Point.

Parameters:
val Number to get square root of.
precisionLoop Number of time to go through the algo to get good presicion in the result. Good value are [10-30] 15 is usualy good.
Returns:
Square root of val in Fixed Point.
Note:
Iterative process, can be slow, use with caution.

static int Math_Tan ( int  angle  )  [static, package, inherited]

Tangent.

Parameters:
angle - Angle in fixed point 0=0 256=360
Returns:
Tangent value of the angle.

Variable Documentation

final int Math_Angle180 = Math_DegreeToFixedPointAngle(180) [static, package, inherited]

180 in fixed point

final int Math_Angle270 = Math_DegreeToFixedPointAngle(270) [static, package, inherited]

270 in fixed point

final int Math_Angle360 = Math_DegreeToFixedPointAngle(360) [static, package, inherited]

360 in fixed point

final int Math_Angle90 = Math_DegreeToFixedPointAngle(90) [static, package, inherited]

90 in fixed point

final int Math_AngleMUL = 1 << GLLibConfig.math_angleFixedPointBase [static, package, inherited]

angle fixed point multiplier eg one degree in fixed point base.(not equal to Math_DegreeToFixedPointAngle(1))

final int Math_FixedPoint_E = 1459366444 >> (29 - GLLibConfig.math_fixedPointBase) [static, package, inherited]

final int Math_FixedPoint_PI = 1686629713 >> (29 - GLLibConfig.math_fixedPointBase) [static, package, inherited]

final int MATH_INTERSECT_NO_INTERSECT = 0 [static, package, inherited]

final int MATH_INTERSECT_ONE_POINT = (1 << 1) [static, package, inherited]

final int MATH_INTERSECT_TWO_POINTS = (1 << 2) [static, package, inherited]

final int MATH_SEGMENTINTERSECT_COLLINEAR = -1 [static, package, inherited]

return value of Math_segmentIntersect if there is no or full intersection because both segment are colinear

final int MATH_SEGMENTINTERSECT_DO_INTERSECT = 1 [static, package, inherited]

return value of Math_segmentIntersect if there is an intersection

final int MATH_SEGMENTINTERSECT_DONT_INTERSECT = 0 [static, package, inherited]

return value of Math_segmentIntersect if there is no intersection

int s_math_bezierX [static, package, inherited]

x coordinate of bezier interpolated value through Math_Bezier2D or Math_Bezier3D

int s_math_bezierY [static, package, inherited]

y coordinate of bezier interpolated value through Math_Bezier2D or Math_Bezier3D

int s_math_bezierZ [static, package, inherited]

z coordinate of bezier interpolated value through Math_Bezier3D

int s_Math_distPointLineX [static, package, inherited]

x coordinate of orthogonal projection of point on a segment using Math_distPointLine

int s_Math_distPointLineY [static, package, inherited]

y coordinate of orthogonal projection of point on a segment using Math_distPointLine

final int s_math_F_05 = (s_math_F_1>>1) [static, package, inherited]

Fixed point value for number 0.5.

final int s_math_F_1 = 1 << GLLibConfig.math_fixedPointBase [static, package, inherited]

Fixed point value for number 1.

int s_Math_intersectPoints[][] = new int[2][2] [static, package, inherited]

int s_Math_intersectX [static, package, inherited]

x coordinate of intersection point of 2 segment using Math_segmentIntersect

int s_Math_intersectY [static, package, inherited]

y coordinate of intersection point of 2 segment using Math_segmentIntersect

java.util.Random s_math_random [static, package, inherited]

Random number generator.

Generated on Tue Sep 23 23:05:30 2008 for GLLib by  doxygen 1.5.2

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