skia2/docs/SkIPoint_Reference.bmh
Cary Clark 09d80c0337 docs with more pop
Replace a hunk of documentation in docs/*.bmh
with #Populate, which instructs bookmaker to
retrieve the documentation from include/core.

Check spelling for all documentation retrieved
from include/core against Skia declarations
and a list of words in spelling.txt.

TBR=caryclark@google.com
Docs-Preview: https://skia.org/?cl=163491
Bug: skia:
Change-Id: If057c3a1336e312ad59c084a3a130f0276802496
Reviewed-on: https://skia-review.googlesource.com/c/163491
Commit-Queue: Cary Clark <caryclark@skia.org>
Reviewed-by: Cary Clark <caryclark@skia.org>
Auto-Submit: Cary Clark <caryclark@skia.org>
2018-10-31 16:45:32 +00:00

403 lines
9.7 KiB
Plaintext

#Topic IPoint
#Alias IPoints ##
#Alias IPoint_Reference ##
#Struct SkIPoint
#Code
#Populate
##
SkIPoint holds two 32-bit integer coordinates.
#Member int32_t fX
#Line # x-axis value ##
x-axis value used by IPoint.
##
#Member int32_t fY
#Line # y-axis value ##
y-axis value used by IPoint.
##
# ------------------------------------------------------------------------------
#Method static constexpr SkIPoint Make(int32_t x, int32_t y)
#In Constructors
#Line # constructs from integer inputs ##
#Populate
#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
#Method ##
# ------------------------------------------------------------------------------
#Subtopic Property
#Line # member values ##
#Subtopic Property ##
#Method int32_t x() const
#In Property
#Line # returns fX ##
#Populate
#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()
#Method ##
# ------------------------------------------------------------------------------
#Method int32_t y() const
#In Property
#Line # returns fY ##
#Populate
#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()
#Method ##
# ------------------------------------------------------------------------------
#Method bool isZero() const
#In Property
#Line # returns true if both members equal zero ##
#Populate
#Example
SkIPoint pt = { 0, -0};
SkDebugf("pt.isZero() == %s\n", pt.isZero() ? "true" : "false");
#StdOut
pt.isZero() == true
##
##
#SeeAlso SkPoint::isZero
#Method ##
# ------------------------------------------------------------------------------
#Subtopic Set
#Line # replaces all values ##
##
#Method void set(int32_t x, int32_t y)
#In Set
#Line # sets to integer input ##
#Populate
#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
#Method ##
# ------------------------------------------------------------------------------
#Method SkIPoint operator-()_const
#Line # reverses sign of IPoint ##
#Populate
#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)
#Line # adds IVector to IPoint ##
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)
#Line # subtracts IVector from IPoint ##
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
#In Operators
#Line # returns true if members are equal ##
#Populate
#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)
#Line # returns true if IPoints are equal ##
#Populate
#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)
#Line # returns true if IPoints are unequal ##
#Populate
#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)
#Line # returns IVector between IPoints ##
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)
#Line # returns IPoint offset by IVector ##
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 ##
#Subtopic IVector
#Line # alias for IPoint ##
#Alias IVector ##
#Alias IVectors ##
#Typedef SkIPoint SkIVector
#Line # alias for IPoint ##
#Code
typedef SkIPoint SkIVector;
##
SkIVector provides an alternative name for SkIPoint. SkIVector and SkIPoint
can be used interchangeably for all purposes.
#Typedef ##
##
#Topic IPoint ##