scummvm/common/rect.h
Bartosz Gentkowski 3ff21ad8c2 DOXYGEN: Further doc updates in high priority files
Adding, editing, updating doxygen comments in header files:

- common/archive.h
- common/array.h
- common/config-manager.h
- common/list.h
- common/random.h
- common/rect.h
- common/savefile.h
2020-11-07 18:19:09 +00:00

401 lines
11 KiB
C++

/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
*/
#ifndef COMMON_RECT_H
#define COMMON_RECT_H
#include "common/scummsys.h"
#include "common/util.h"
#include "common/debug.h"
#define PRINT_RECT(x) (x).left,(x).top,(x).right,(x).bottom
namespace Common {
/**
* @defgroup common_rect Rectangular zones
* @ingroup common
*
* @brief API for operations on rectangular zones.
*
* @{
*/
/**
* Simple class for handling both 2D position and size.
*/
struct Point {
int16 x; /*!< The horizontal position of the point. */
int16 y; /*!< The vertical position of the point. */
Point() : x(0), y(0) {}
/**
* Create a point with position defined by @p x1 and @p y1.
*/
Point(int16 x1, int16 y1) : x(x1), y(y1) {}
/**
* Determine whether the position of two points is the same.
*/
bool operator==(const Point &p) const { return x == p.x && y == p.y; }
/**
* Determine whether the position of two points is not the same.
*/
bool operator!=(const Point &p) const { return x != p.x || y != p.y; }
/**
* Create a point by adding the @p delta value to a point.
*/
Point operator+(const Point &delta) const { return Point(x + delta.x, y + delta.y); }
/**
* Create a point by subtracting the @p delta value from a point.
*/
Point operator-(const Point &delta) const { return Point(x - delta.x, y - delta.y); }
/**
* Create a point by dividing a point by the (int) @p divisor value.
*/
Point operator/(int divisor) const { return Point(x / divisor, y / divisor); }
/**
* Create a point by multiplying a point by the (int) @p multiplier value.
*/
Point operator*(int multiplier) const { return Point(x * multiplier, y * multiplier); }
/**
* Create a point by dividing a point by the (double) @p divisor value.
*/
Point operator/(double divisor) const { return Point(x / divisor, y / divisor); }
/**
* Create a point by multiplying a point by the (double) @p multiplier value.
*/
Point operator*(double multiplier) const { return Point(x * multiplier, y * multiplier); }
/**
* Change a point's position by adding @p delta to its x and y coordinates.
*/
void operator+=(const Point &delta) {
x += delta.x;
y += delta.y;
}
/**
* Change a point's position by subtracting @p delta from its x and y arguments.
*/
void operator-=(const Point &delta) {
x -= delta.x;
y -= delta.y;
}
/**
* Return the square of the distance between this point and the point @p p.
*
* @param p The other point.
* @return The distance between this and @p p.
*/
uint sqrDist(const Point &p) const {
int diffx = ABS(p.x - x);
if (diffx >= 0x1000)
return 0xFFFFFF;
int diffy = ABS(p.y - y);
if (diffy >= 0x1000)
return 0xFFFFFF;
return uint(diffx * diffx + diffy * diffy);
}
};
static inline Point operator*(int multiplier, const Point &p) { return Point(p.x * multiplier, p.y * multiplier); }
static inline Point operator*(double multiplier, const Point &p) { return Point(p.x * multiplier, p.y * multiplier); }
/**
* Simple class for handling a rectangular zone.
*
* Note: This implementation is built around the assumption that (top,left) is
* part of the rectangle, but (bottom,right) is not. This is reflected in
* various methods, including contains(), intersects(), and others.
*
* Another very widespread approach to rectangle classes treats (bottom,right)
* also as a part of the rectangle.
*
* Conceptually, both are sound, but the approach we use saves many intermediate
* computations (like computing the height in our case is done by doing this:
* height = bottom - top;
* while in the alternate system, it would be
* height = bottom - top + 1;
*
* When writing code using our Rect class, always keep this principle in mind!
*/
struct Rect {
int16 top, left; /*!< The point at the top left of the rectangle (part of the Rect). */
int16 bottom, right; /*!< The point at the bottom right of the rectangle (not part of the Rect). */
Rect() : top(0), left(0), bottom(0), right(0) {}
/**
* Create a rectangle with the top-left corner at position (0, 0) and the given width @p w and height @p h.
*/
Rect(int16 w, int16 h) : top(0), left(0), bottom(h), right(w) {}
/**
* Create a rectangle with the top-left corner at the given position (x1, y1)
* and the bottom-right corner at the position (x2, y2).
*
* The @p x2 value must be greater or equal @p x1 and @p y2 must be greater or equal @p y1.
*/
Rect(int16 x1, int16 y1, int16 x2, int16 y2) : top(y1), left(x1), bottom(y2), right(x2) {
assert(isValidRect());
}
/**
* Check if two rectangles are identical.
*
* @return True if the rectangles are identical, false otherwise.
*/
bool operator==(const Rect &rhs) const { return equals(rhs); }
/**
* Check if two rectangles are different.
*
* @return True if the rectangles are different, false otherwise.
*/
bool operator!=(const Rect &rhs) const { return !equals(rhs); }
int16 width() const { return right - left; } /*!< Return the width of a rectangle. */
int16 height() const { return bottom - top; } /*!< Return the height of a rectangle. */
void setWidth(int16 aWidth) { /*!< Set the width to @p aWidth value. */
right = left + aWidth;
}
void setHeight(int16 aHeight) { /*!< Set the height to @p aHeight value. */
bottom = top + aHeight;
}
/**
* Check if the given position is inside this rectangle.
*
* @param x The horizontal position to check.
* @param y The vertical position to check.
*
* @return True if the given position is inside this rectangle, false otherwise.
*/
bool contains(int16 x, int16 y) const {
return (left <= x) && (x < right) && (top <= y) && (y < bottom);
}
/**
* Check if the given point is inside this rectangle.
*
* @param p The point to check.
*
* @return True if the given point is inside this rectangle, false otherwise.
*/
bool contains(const Point &p) const {
return contains(p.x, p.y);
}
/**
* Check if the given Rect is contained inside this rectangle.
*
* @param r The rectangle to check.
*
* @return True if the given Rect is inside, false otherwise.
*/
bool contains(const Rect &r) const {
return (left <= r.left) && (r.right <= right) && (top <= r.top) && (r.bottom <= bottom);
}
/**
* Check if the given Rect is equal to this one.
*
* @param r The rectangle to check.
*
* @return true If the given Rect is equal, false otherwise.
*/
bool equals(const Rect &r) const {
return (left == r.left) && (right == r.right) && (top == r.top) && (bottom == r.bottom);
}
/**
* Check if the given rectangle intersects with this rectangle.
*
* @param r The rectangle to check.
*
* @return True if the given rectangle has a non-empty intersection with
* this rectangle, false otherwise.
*/
bool intersects(const Rect &r) const {
return (left < r.right) && (r.left < right) && (top < r.bottom) && (r.top < bottom);
}
/**
* Find the intersecting rectangle between this rectangle and the given rectangle.
*
* @param r The intersecting rectangle.
*
* @return The intersection of the rectangles or an empty rectangle if not intersecting.
*/
Rect findIntersectingRect(const Rect &r) const {
if (!intersects(r))
return Rect();
return Rect(MAX(r.left, left), MAX(r.top, top), MIN(r.right, right), MIN(r.bottom, bottom));
}
/**
* Extend this rectangle so that it contains @p r.
*
* @param r The rectangle to extend by.
*/
void extend(const Rect &r) {
left = MIN(left, r.left);
right = MAX(right, r.right);
top = MIN(top, r.top);
bottom = MAX(bottom, r.bottom);
}
/**
* Extend this rectangle in all four directions by the given number of pixels.
*
* @param offset The size to grow by.
*/
void grow(int16 offset) {
top -= offset;
left -= offset;
bottom += offset;
right += offset;
}
/**
* Clip this rectangle with another rectangle @p r.
*/
void clip(const Rect &r) {
assert(isValidRect());
assert(r.isValidRect());
if (top < r.top) top = r.top;
else if (top > r.bottom) top = r.bottom;
if (left < r.left) left = r.left;
else if (left > r.right) left = r.right;
if (bottom > r.bottom) bottom = r.bottom;
else if (bottom < r.top) bottom = r.top;
if (right > r.right) right = r.right;
else if (right < r.left) right = r.left;
}
/**
* Reduce the dimensions of this rectangle by setting max width and max heigth.
*/
void clip(int16 maxw, int16 maxh) {
clip(Rect(0, 0, maxw, maxh));
}
/**
* Check if the rectangle is empty (its width or length is 0) or invalid (its width or length are negative).
*
* @retval true The rectangle is empty or invalid.
* @retval false The rectangle is valid and not empty.
*/
bool isEmpty() const {
return (left >= right || top >= bottom);
}
/**
* Check if this is a valid rectangle.
*/
bool isValidRect() const {
return (left <= right && top <= bottom);
}
/**
* Move this rectangle to the position defined by @p x, @p y.
*/
void moveTo(int16 x, int16 y) {
bottom += y - top;
right += x - left;
top = y;
left = x;
}
/**
* Move the rectangle by the given delta x and y values.
*/
void translate(int16 dx, int16 dy) {
left += dx; right += dx;
top += dy; bottom += dy;
}
/**
* Move this rectangle to the position of the point @p p.
*/
void moveTo(const Point &p) {
moveTo(p.x, p.y);
}
/**
* Print debug messages related to this class.
*/
void debugPrint(int debuglevel = 0, const char *caption = "Rect:") const {
debug(debuglevel, "%s %d, %d, %d, %d", caption, left, top, right, bottom);
}
/**
* Create a rectangle around the given center.
* @note The center point is rounded up and left when given an odd width and height.
*/
static Rect center(int16 cx, int16 cy, int16 w, int16 h) {
int x = cx - w / 2, y = cy - h / 2;
return Rect(x, y, x + w, y + h);
}
/**
* Given target surface with size clip, this function ensures that
* blit arguments @p dst and @p rect are within the @p clip rectangle.
* @param dst Blit destination coordinates.
* @param rect Blit source rectangle.
* @param clip Clip rectangle (size of destination surface).
*/
static bool getBlitRect(Point &dst, Rect &rect, const Rect &clip) {
if (dst.x < clip.left) {
rect.left += clip.left - dst.x;
dst.x = clip.left;
}
if (dst.y < clip.top) {
rect.top += clip.top - dst.y;
dst.y = clip.top;
}
int right = dst.x + rect.right;
if (right > clip.right)
rect.right -= right - clip.right;
int bottom = dst.y + rect.bottom;
if (bottom > clip.bottom)
rect.bottom -= bottom - clip.bottom;
return !rect.isEmpty();
}
};
/** @} */
} // End of namespace Common
#endif