Programmer Guide/Command Reference/EVAL/pgitest: Difference between revisions

Latest revision as of 19:10, 21 April 2011

Check the relation (outside, inside, overlap) of a given point, line or simple polygon p to the polygon x.

Usage 1

pgitest(X, IX, PX_scalar, PY_scalar)

X: a closed point-list or a polygon-stream defining one or more polygons.
IX: The index of the polygon of X to be tested; 0 ≤ IX < pgget(X)
PX, PY: The point P=<PX,PY> to be tested.

Result 1: The result r is a scaler.

r=0	... point P is outside the polygon X_IX
r=1	... point P is inside the polygon X_IX

Usage 2

pgitest(X, IX, PX_scalar, PY_vector)

pgitest(X, IX, PX_vector, PY_scalar)

pgitest(X, IX, PX_vector, PY_vector)

PX, PY: The points P[i]=<PX[i],PY[i]> to be tested. One of these arguments must be a vector.

Result 2: The result r is a vector containing the test result for each point P[i].

r[i]=0	... point P[i] is outside the polygon X_IX
r[i]=1	... point P[i] is inside the polygon X_IX

Usage 3

pgitest(X, IX, PX1_scalar, PY1_scalar), PX2_scalar, PY2_scalar)

PX1, PY1, PX2, PY2: The points <PX1,PY1> and <PX2,PY2> defining the line P to be tested.

Result 3: The result r is a scalar.

r=0	... the line P is outside the polygon X_IX
r=1	... the line P is inside the polygon X_IX
r=2	... the line P intersects the polygon X_IX

Usage 4

pgitest(X, IX, P, IP)

P: a closed point-list or a polygon-stream defining one or more polygons.
IP: The index of the polygon of P to be tested; 0 ≤ IP < pgget(P))

Result 4: The result r is a scalar.

r=0	... the polygon P_IP is outside the polygon X_IX
r=1	... the polygon P_IP is included in the polygon X_IX
r=2	... the polygons P_IP and X_IX are partly overlapping
r=3	... the polygon X_IX is included in the polygon P_IP

See also: pginit, pgget, pgiline, pgxgrid, pgsplit, pgtrans, pghull

Programmer Guide/Command Reference/EVAL/pgitest: Difference between revisions

Latest revision as of 19:10, 21 April 2011

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@@ Line 1: / Line 1: @@
 {{DISPLAYTITLE:{{SUBPAGENAME}}}}
-=====pgitest - detect point in polygon=====
+Check the relation (outside, inside, overlap) of a given point, line or simple polygon ''p'' to the polygon ''x''.
+----
+;Usage 1:
+:<code>pgitest(<var>X</var>, <var>IX</var>, <var>PX<sub>scalar</sub></var>, <var>PY<sub>scalar</sub></var>)</code>
+:;<var>X</var>:a [[../#polygons|closed point-list]] or a [[../#polygons|polygon-stream]] defining one or more polygons.
+:;<var>IX</var>:The index of the polygon of ''X'' to be tested; 0 &le; <var>IX</var> < <code>[[../pgget|pgget]](''X'')</code>
+:;<var>PX, PY</var>: The point ''P''=<''PX'',''PY''> to be tested.
+;Result 1: The result ''r'' is a scaler.
+::{|class="keinrahmen"
+|''r''='''0''' || ... point ''P'' is outside the polygon ''X<sub>IX</sub>''
+|-
+|''r''='''1''' || ... point ''P'' is inside the polygon ''X<sub>IX</sub>''
+|}
+----
+;Usage 2:
+:<code>pgitest(<var>X</var>, <var>IX</var>, <var>PX<sub>scalar</sub></var>, <var>PY<sub>vector</sub></var>)</code>
+:<code>pgitest(<var>X</var>, <var>IX</var>, <var>PX<sub>vector</sub></var>, <var>PY<sub>scalar</sub></var>)</code>
+:<code>pgitest(<var>X</var>, <var>IX</var>, <var>PX<sub>vector</sub></var>, <var>PY<sub>vector</sub></var>)</code>
+:;<var>PX, PY</var>: The points ''P''[i]=<''PX''[i],''PY''[i]> to be tested. One of these arguments must be a vector.
+;Result 2: The result ''r'' is a vector containing the test result for each point ''P''[i].
+::{|class="keinrahmen"
+|''r''[i]='''0''' || ... point ''P''[i] is outside the polygon ''X<sub>IX</sub>''
+|-
+|''r''[i]='''1''' || ... point ''P''[i] is inside the polygon ''X<sub>IX</sub>''
+|}
+----
+;Usage 3:
+:<code>pgitest(<var>X</var>, <var>IX</var>, <var>PX1<sub>scalar</sub></var>, <var>PY1<sub>scalar</sub></var>), <var>PX2<sub>scalar</sub></var>, <var>PY2<sub>scalar</sub></var>)</code>
+:;<var>PX1, PY1, PX2, PY2</var>: The points <''PX1'',''PY1''> and <''PX2'',''PY2''> defining the line ''P'' to be tested.
+;Result 3: The result ''r'' is a scalar.
+::{|class="keinrahmen"
+|''r''='''0''' || ... the line ''P'' is outside the polygon ''X<sub>IX</sub>''
+|-
+|''r''='''1''' || ... the line ''P'' is inside the polygon ''X<sub>IX</sub>''
+|-
+|''r''='''2''' || ... the line ''P'' intersects the polygon ''X<sub>IX</sub>''
+|}
+----
+;Usage 4:
+:<code>pgitest(<var>X</var>, <var>IX</var>, <var>P</var>, <var>IP</var>)</code>
+:;<var>P</var>:a [[../#polygons|closed point-list]] or a [[../#polygons|polygon-stream]] defining one or more polygons.
+:;<var>IP</var>:The index of the polygon of ''P'' to be tested; 0 &le; <var>IP</var> < <code>[[../pgget|pgget]](''P'')</code>)
+;Result 4: The result ''r'' is a scalar.
+::{|class="keinrahmen"
+|''r''='''0''' || ... the polygon ''P<sub>IP</sub>'' is outside the polygon ''X<sub>IX</sub>''
+|-
+|''r''='''1''' || ... the polygon ''P<sub>IP</sub>'' is included in the polygon ''X<sub>IX</sub>''
+|-
+|''r''='''2''' || ... the polygons ''P<sub>IP</sub>'' and ''X<sub>IX</sub>'' are partly overlapping
+|-
+|''r''='''3''' || ... the polygon ''X<sub>IX</sub>'' is included in the polygon ''P<sub>IP</sub>''
+|}
+----
+;See also: [[../pginit|pginit]], [[../pgget|pgget]], [[../pgiline|pgiline]], [[../pgxgrid|pgxgrid]], [[../pgsplit|pgsplit]], [[../pgtrans|pgtrans]], [[../pghull|pghull]]
-=====Usage:=====
+[[../#Functions|<function list>]]
-<code><var>I</var> := pgITest( {pg_stream|pg_cplist}<var>XS</var>, {number}<var>IX</var>, {number}<var>XP</var>, {number}<var>YP</var> )</code>
-=====Description:=====
-Detect if a point is inside a simple polygon.
-=====Parameters:=====
-;<var>XS</var>
-:The polygon stream containing the simple polygon, or point list describing the simple polygon.
-;<var>IX</var>
-:The index of the polygon describing the simple polygon.
-;<var>XP</var>
-:The x point to test.
-;<var>YP</var>
-:The y point to test.
-=====Result:=====
-<code>0</code> if the point <<var>XP</var>,<var>YP</var>> is outside the polygon <var>XS</var>[<var>IX</var>]
-<code>1</code> if the point <<var>XP</var>,<var>YP</var>> is inside the polygon <var>XS</var>[<var>IX</var>]
-=====Usage:=====
-<code><var>I</var> := pgITest( {pg_stream|pg_cplist}<var>XS</var>, {number}<var>IX</var>, {vector}<var>XP</var>, {vector}<var>YP</var> )</code>
-<code><var>I</var> := pgITest( {pg_stream|pg_cplist}<var>XS</var>, {number}<var>IX</var>, {number}<var>XP</var>, {vector}<var>YP</var> )</code>
-<code><var>I</var> := pgITest( {pg_stream|pg_cplist}<var>XS</var>, {number}<var>IX</var>, {vector}<var>XP</var>, {number}<var>YP</var> )</code>
-=====Description:=====
-Detect if a line is inside a simple polygon.
-=====Parameters:=====
-=====Result:=====
-A vector I with I[j]=0 if <XP[j],YP[j]> is outside the polygon XS[IX] and
-I[j]=1 if <XP[j],YP[j]> is inside the polygon XS[IX]
-=====Usage:=====
-<code>I := pgITest( {pg_stream|pg_cplist}XS, {number}IX, {number}X1, {number}Y1, {number}X2, number{Y2} )</code>
-=====Description:=====
-Detect if a line is inside a simple polygon.
-=====Parameters:=====
-=====Result:=====
-if all points of the line <X1,Y1>..<X2,Y2> are outside the polygon XS[IX]
-if all points of the line <X1,Y1>..<X2,Y2> are inside the polygon XS[IX]
-if the line <X1,Y1>..<X2,Y2> is intersects the polygon XS[IX]
-=====Usage:=====
-<code>I := pgITest( {pg_stream|pg_cplist}XS, {number}IX, {pg_stream|pg_cplist}YS, {number}IY )</code>
-=====Description:=====
-Detect if a simple polygon is inside a simple polygon.
-=====Parameters:=====
-=====Result:=====
-if polygon YS[IX] is outside of polygon XS[IX]
-if polygon YS[IX] is included in polygon XS[IX]
-if polygon YS[IX] and XS[IX] are partly overlapping
-if polygon XS[IX] is included in polygon YS[IX]
-=====pgsplit - split polygon through line=====
-=====Usage:=====
-<code><var>YS</var> := pgSplit( {pg_stream}<var>XS</var>, {number}<var>IX</var>, {number}<var>X1</var>, {number}<var>Y1</var>, {number}<var>X2</var>, {number}<var>Y2</var> )</code>
-=====Description:=====
-Use a line to split a polygon into two polygons.
-=====Result:=====
-The pg_stream <var>YS</var> containing the two polygon parts of the polygon <var>XS</var>[<var>IX</var>]
-=====pgtrans - shift, scale or rotate polygon=====
-=====Usage:=====
-<code><var>YS</var> := pgTrans( {pg_stream}<var>XS</var>, {number}<var>IX</var>, {number}<var>DX</var>=0, {number}<var>DY</var>=0, {number}<var>KX</var>=1, {number}<var>KY</var>=1, {number}<var>A</var>=0)</code>
-=====Description:=====
-Shift (dx/dy) / scale (kx/ky) / rotate polygon (a).
-=====Parameters:=====
-;<var>XS</var>
-:The polygon stream containing the simple polygon, or point list describing the simple polygon.
-;<var>IX</var>
-:The index of the polygon describing the simple polygon.
-;<var>DX</var>
-;<var></var>
-;<var>DY</var>
-;<var></var>
-;<var>KX</var>
-;<var></var>
-;<var>KY</var>
-;<var></var>
-;<var>A</var>
-;<var></var>
-=====Result:=====
-The resulting polygon.