skia2/docs/SkIPoint_Reference.bmh

#Topic IPoint
#Alias IPoints
#Alias IPoint_Reference

#Struct SkIPoint

SkIPoint holds two 32 bit integer coordinates

#Topic Overview

#Subtopic Subtopics
#ToDo manually add subtopics ##
#Table
#Legend
# topics # description ##
#Legend ##
#Table ##
##

#Subtopic Operators
#Table
#Legend
# description                                               # function                             ##
#Legend ##
# SkIPoint operator-()_const                                # Reverses sign of IPoint.             ##
# SkIPoint operator+(const SkIPoint& a, const SkIVector& b) # Returns IPoint offset by IVector.    ##
# SkIVector operator-(const SkIPoint& a, const SkIPoint& b) # Returns IVector between IPoints.     ##
# bool operator!=(const SkIPoint& a, const SkIPoint& b)     # Returns true if IPoints are unequal. ##
# bool operator==(const SkIPoint& a, const SkIPoint& b)     # Returns true if IPoints are equal.   ##
# void operator+=(const SkIVector& v)                       # Adds IVector to IPoint.              ##
# void operator-=(const SkIVector& v)                       # Subtracts IVector from IPoint.       ##
#Table ##
#Subtopic ##

#Subtopic Member_Functions
#Table
#Legend
# description  # function ##
#Legend ##
# Make         # Constructs from integer inputs.          ##
# equals()     # Returns true if members are equal.       ##
# isZero       # Returns true if both members equal zero. ##
# set()        # Sets to integer input.                   ##
# x()          # Returns fX.                              ##
# y()          # Returns fY.                              ##
#Table ##
#Subtopic ##

#Topic ##

#Member int32_t  fX
x-axis value used by IPoint.
##

#Member int32_t  fY
y-axis value used by IPoint.
##

# ------------------------------------------------------------------------------

#Method static constexpr SkIPoint Make(int32_t x, int32_t y)

Sets fX to x, fY to y.

#Param x  integer x-axis value of constructed IPoint ##
#Param y  integer y-axis value of constructed IPoint ##

#Return IPoint (x, y) ##

#Example
SkIPoint pt1 = {45, 66};
SkIPoint pt2 = SkIPoint::Make(45, 66);
SkDebugf("pt1 %c= pt2\n", pt1 == pt2 ? '=' : '!');
#StdOut
pt1 == pt2
##
##

#SeeAlso set() SkPoint::iset() SkPoint::Make SkIPoint16::Make

#Method ##

# ------------------------------------------------------------------------------

#Method int32_t x() const

Returns x-axis value of IPoint.

#Return fX ##

#Example
SkIPoint pt1 = {45, 66};
SkDebugf("pt1.fX %c= pt1.x()\n", pt1.fX == pt1.x() ? '=' : '!');
#StdOut
pt1.fX == pt1.x()
##
##

#SeeAlso y() SkPoint::x() SkIPoint16::x()

#Method ##

# ------------------------------------------------------------------------------

#Method int32_t y() const

Returns y-axis value of IPoint.

#Return fY ##

#Example
SkIPoint pt1 = {45, 66};
SkDebugf("pt1.fY %c= pt1.y()\n", pt1.fY == pt1.y() ? '=' : '!');
#StdOut
pt1.fY == pt1.y()
##
##

#SeeAlso x() SkPoint::y() SkIPoint16::y()

#Method ##

# ------------------------------------------------------------------------------

#Method bool isZero() const

Returns true if fX and fY are both zero.

#Return true if fX is zero and fY is zero ##

#Example
SkIPoint pt = { 0, -0};
SkDebugf("pt.isZero() == %s\n", pt.isZero() ? "true" : "false");
#StdOut
pt.isZero() == true
##
##

#SeeAlso SkPoint::isZero

#Method ##

# ------------------------------------------------------------------------------

#Method void set(int32_t x, int32_t y)

Sets fX to x and fY to y.

#Param x  new value for fX ##
#Param y  new value for fY ##

#Example
SkIPoint pt1, pt2 = { SK_MinS32, SK_MaxS32 };
pt1.set(SK_MinS32, SK_MaxS32);
SkDebugf("pt1 %c= pt2\n", pt1 == pt2 ? '=' : '!');
#StdOut
pt1 == pt2
##
##

#SeeAlso Make SkIPoint16::set

#Method ##

# ------------------------------------------------------------------------------

#Method SkIPoint operator-()_const

Returns IPoint changing the signs of fX and fY.

#Return IPoint as (-fX, -fY) ##

#Example
SkIPoint test[] = { {0, -0}, {-1, -2},
                   { SK_MaxS32, SK_MinS32 },
                   { SK_NaN32, -SK_NaN32 } };
for (const SkIPoint& pt : test) {
    SkIPoint negPt = -pt;
    SkDebugf("pt: %d, %d  negate: %d, %d\n", pt.fX, pt.fY, negPt.fX, negPt.fY);
}
#StdOut
pt: 0, 0  negate: 0, 0
pt: -1, -2  negate: 1, 2
pt: 2147483647, -2147483647  negate: -2147483647, 2147483647
pt: -2147483648, -2147483648  negate: -2147483648, -2147483648
##
##

#SeeAlso operator-(const SkIPoint& a, const SkIPoint& b) operator-=(const SkIVector& v) SkPoint::operator-()_const

#Method ##

# ------------------------------------------------------------------------------

#Method void operator+=(const SkIVector& v)

Offsets IPoint by IVector v. Sets IPoint to
#Formula
(fX + v.fX, fY + v.fY)
##
.

#Param v  IVector to add ##

#Example
#Height 64
    auto draw_lines = [=](const SkIPoint pts[], size_t count, SkPaint& paint) -> void {
        for (size_t i = 0; i < count - 1; ++i) {
            SkPoint p0, p1;
            p0.iset(pts[i]);
            p1.iset(pts[i + 1]);
            canvas->drawLine(p0, p1, paint);
        }
    };
    SkIPoint points[] = { { 3, 1 }, { 4, 2 }, { 5, 1 }, { 7, 3 } };
    SkPaint paint;
    paint.setAntiAlias(true);
    paint.setStyle(SkPaint::kStroke_Style);
    canvas->scale(30, 15);
    draw_lines(points, SK_ARRAY_COUNT(points), paint);
    points[1] += {1, 1};
    points[2] += {-1, -1};
    paint.setColor(SK_ColorRED);
    draw_lines(points, SK_ARRAY_COUNT(points), paint);
##

#SeeAlso operator+(const SkIPoint& a, const SkIVector& b) SkPoint::operator+=(const SkVector& v)

#Method ##

# ------------------------------------------------------------------------------

#Method void operator-=(const SkIVector& v)

Subtracts IVector v from IPoint. Sets IPoint to:
#Formula
(fX - v.fX, fY - v.fY)
##
.

#Param v  IVector to subtract ##

#Example
#Height 64
    auto draw_lines = [=](const SkIPoint pts[], size_t count, SkPaint& paint) -> void {
        for (size_t i = 0; i < count - 1; ++i) {
            SkPoint p0, p1;
            p0.iset(pts[i]);
            p1.iset(pts[i + 1]);
            canvas->drawLine(p0, p1, paint);
        }
    };
    SkIPoint points[] = { { 3, 1 }, { 4, 2 }, { 5, 1 }, { 7, 3 } };
    SkPaint paint;
    paint.setAntiAlias(true);
    paint.setStyle(SkPaint::kStroke_Style);
    canvas->scale(30, 15);
    draw_lines(points, SK_ARRAY_COUNT(points), paint);
    points[1] -= {1, 1};
    points[2] -= {-1, -1};
    paint.setColor(SK_ColorRED);
    draw_lines(points, SK_ARRAY_COUNT(points), paint);
##

#SeeAlso operator-(const SkIPoint& a, const SkIPoint& b) SkPoint::operator-=(const SkVector& v)

#Method ##

# ------------------------------------------------------------------------------

#Method bool equals(int32_t x, int32_t y) const

Returns true if IPoint is equivalent to IPoint constructed from (x, y).

#Param x  value compared with fX ##
#Param y  value compared with fY ##

#Return true if IPoint equals (x, y) ##

#Example
SkIPoint test[] = { {0, -0}, {-1, -2}, {SK_MaxS32, -1}, {SK_NaN32, -1} };
for (const SkIPoint& pt : test) {
    SkDebugf("pt: %d, %d  %c= pt\n", pt.fX, pt.fY, pt.equals(pt.fX, pt.fY) ? '=' : '!');
}
#StdOut
pt: 0, 0  == pt
pt: -1, -2  == pt
pt: 2147483647, -1  == pt
pt: -2147483648, -1  == pt
##
##

#SeeAlso operator==(const SkIPoint& a, const SkIPoint& b)

#Method ##

# ------------------------------------------------------------------------------

#Method bool operator==(const SkIPoint& a, const SkIPoint& b)

Returns true if a is equivalent to b.

#Param a  IPoint to compare ##
#Param b  IPoint to compare ##

#Return true if a.fX == b.fX and a.fY == b.fY ##

#Example
SkIPoint test[] = { {0, -0}, {-1, -2}, {SK_MaxS32, -1}, {SK_NaN32, -1} };
for (const SkIPoint& pt : test) {
    SkDebugf("pt: %d, %d  %c= pt\n", pt.fX, pt.fY, pt == pt ? '=' : '!');
}
#StdOut
pt: 0, 0  == pt
pt: -1, -2  == pt
pt: 2147483647, -1  == pt
pt: -2147483648, -1  == pt
##
##

#SeeAlso equals() operator!=(const SkIPoint& a, const SkIPoint& b)

#Method ##

# ------------------------------------------------------------------------------

#Method bool operator!=(const SkIPoint& a, const SkIPoint& b)

Returns true if a is not equivalent to b.

#Param a  IPoint to compare ##
#Param b  IPoint to compare ##

#Return true if a.fX != b.fX or a.fY != b.fY ##

#Example
SkIPoint test[] = { {0, -0}, {-1, -2}, {SK_MaxS32, -1}, {SK_NaN32, -1} };
for (const SkIPoint& pt : test) {
    SkDebugf("pt: %d, %d  %c= pt\n", pt.fX, pt.fY, pt != pt ? '!' : '=');
}
#StdOut
pt: 0, 0  == pt
pt: -1, -2  == pt
pt: 2147483647, -1  == pt
pt: -2147483648, -1  == pt
##
##

#SeeAlso operator==(const SkIPoint& a, const SkIPoint& b) equals()

#Method ##

# ------------------------------------------------------------------------------

#Method SkIVector operator-(const SkIPoint& a, const SkIPoint& b)

Returns IVector from b to a; computed as
#Formula
(a.fX - b.fX, a.fY - b.fY)
##
.

Can also be used to subtract IVector from IVector, returning IVector.

#Param a  IPoint or IVector to subtract from ##
#Param b  IVector to subtract ##

#Return IVector from b to a ##

#Example
#Height 64
    auto draw_lines = [=](const SkIPoint pts[], size_t count, SkPaint& paint) -> void {
        for (size_t i = 0; i < count - 1; ++i) {
            SkPoint p0, p1;
            p0.iset(pts[i]);
            p1.iset(pts[i + 1]);
            canvas->drawLine(p0, p1, paint);
        }
    };
    SkIPoint points[] = { { 3, 1 }, { 4, 2 }, { 5, 1 }, { 7, 3 } };
    SkPaint paint;
    paint.setAntiAlias(true);
    paint.setStyle(SkPaint::kStroke_Style);
    canvas->scale(30, 15);
    draw_lines(points, SK_ARRAY_COUNT(points), paint);
    points[1] += points[0] - points[3];
    points[2] -= points[1] - points[0];
    paint.setColor(SK_ColorRED);
    draw_lines(points, SK_ARRAY_COUNT(points), paint);
##

#SeeAlso operator-=(const SkIVector& v)

#Method ##

# ------------------------------------------------------------------------------

#Method SkIPoint operator+(const SkIPoint& a, const SkIVector& b)

Returns IPoint resulting from IPoint a offset by IVector b, computed as:
#Formula
(a.fX + b.fX, a.fY + b.fY)
##
.

Can also be used to offset IPoint b by IVector a, returning IPoint.
Can also be used to add IVector to IVector, returning IVector.

#Param a  IPoint or IVector to add to ##
#Param b  IPoint or IVector to add ##

#Return IPoint equal to a offset by b ##

#Example
#Height 128
    auto draw_lines = [=](const SkIPoint pts[], size_t count, SkPaint& paint) -> void {
        for (size_t i = 0; i < count - 1; ++i) {
            SkPoint p0, p1;
            p0.iset(pts[i]);
            p1.iset(pts[i + 1]);
            canvas->drawLine(p0, p1, paint);
        }
    };
    SkIPoint points[] = { { 3, 1 }, { 4, 2 }, { 5, 1 }, { 7, 3 } };
    SkPaint paint;
    paint.setAntiAlias(true);
    paint.setStyle(SkPaint::kStroke_Style);
    canvas->scale(30, 15);
    draw_lines(points, SK_ARRAY_COUNT(points), paint);
    SkIPoint mod = {4, 1};
    for (auto& point : points) {
        point = point + mod;
        mod.fX -= 1;
        mod.fY += 1;
    }
    paint.setColor(SK_ColorRED);
    draw_lines(points, SK_ARRAY_COUNT(points), paint);
##

#SeeAlso operator+=(const SkIVector& v)

#Method ##

#Struct SkIPoint ##

#Topic IPoint ##

#Topic IVector
    #Alias IVectors
    #Typedef SkIPoint SkIVector
    #Typedef ##
##