static void merge_dirty_rects(struct drm_clip_rect *rects, int *count)
{
int a, b;
for (a = 0; a < *count - 1; ++a) {
for (b = a + 1; b < *count;) {
/* collapse to bounding rect if it is fewer pixels */
const int area_a = rect_area(&rects[a]);
const int area_b = rect_area(&rects[b]);
struct drm_clip_rect bounding_rect = rects[a];
expand_rect(&bounding_rect, &rects[b]);
if (rect_area(&bounding_rect) <= area_a + area_b) {
rects[a] = bounding_rect;
rects[b] = rects[*count - 1];
/* repass */
b = a + 1;
--*count;
} else {
++b;
}
}
}
}
double trap_area(double short_side, double long_side, double height) {
//caculate the area of a trapezoid
//you can store the result of a function in a variable
//to do so just assign a variable to a function that returns something
double r_area = rect_area(short_side, height); //the area of the center square
double tri_base = (long_side - short_side) / 2.0;
double tri_areas = tri_area(tri_base, height) * 2;//the area of the triable parts
double t_area = r_area + tri_areas;
return t_area;
}
double square_area(double length) {
//calculate the area of a square
//to call a function write its name(first argument, second argument, ...)
//when you call a function you immediately jump to that function and execute the code that
//is in that function. After that function returns you come back to where you called it
//and proceed from where you left off
//a function can call other functions
//it is perfectly ok
return rect_area(length, length);
}
//functions don't always have to return a value or accept arguments
//if a function doesn't return a value you should place void in front of it
void do_rect() {
double height, width, area;
printf("Please enter the width of the rectangle: ");
scanf("%lf", &width);
printf("Please enter the height of the rectangle: ");
scanf("%lf", &height);
area = rect_area(width, height);
printf("The area of a rectangle with height %.2lf and width %.2lf is %.2lf\n", height, width, area);
//if a function doesn't return anything you don't need a return staement
}//do_rect
int main(int argc, char *argv[])
{
struct rectangle rect = get_rect();
print_rect(rect);
printf("The area of this rectangle: %d\n", rect_area(rect));
printf("Enter a point to check if in the rectangle:");
struct point po = get_point();
if (point_in_rect(po, rect)) {
printf("The point is in the rectangle\n");
} else {
printf("The point is not in the rectangle\n");
}
return 0;
}
double tri_area(double base, double height) {
//calculate the area of a triangle
return rect_area(base, height) / 2.0;
}