Delete no-longer used functions

This commit is contained in:
Grant Sanderson
2023-01-17 17:46:23 -08:00
parent 5e1a02d2ce
commit c7e32e847d

View File

@ -1,32 +1,3 @@
float cross2d(vec2 v, vec2 w){
return v.x * w.y - w.x * v.y;
}
vec2 complex_div(vec2 v, vec2 w){
return vec2(dot(v, w), cross2d(w, v)) / dot(w, w);
}
vec2 xs_on_clean_parabola(vec2 b0, vec2 b1, vec2 b2){
/*
Given three control points for a quadratic bezier,
this returns the two values (x0, x2) such that the
section of the parabola y = x^2 between those values
is isometric to the given quadratic bezier.
Adapated from https://github.com/raphlinus/raphlinus.github.io/blob/master/_posts/2019-12-23-flatten-quadbez.md
*/
vec2 dd = normalize(2 * b1 - b0 - b2);
float u0 = dot(b1 - b0, dd);
float u2 = dot(b2 - b1, dd);
float cp = cross2d(b2 - b0, dd);
return vec2(u0 / cp, u2 / cp);
}
vec2 xs_on_clean_parabola(vec3 b0, vec3 b1, vec3 b2){
/*
Given three control points for a quadratic bezier,
@ -47,34 +18,6 @@ vec2 xs_on_clean_parabola(vec3 b0, vec3 b1, vec3 b2){
}
mat3 map_point_pairs(vec2 src0, vec2 src1, vec2 dst0, vec2 dst1){
/*
Returns an orthogonal matrix which will map
src0 onto dst0 and src1 onto dst1.
*/
mat3 shift1 = mat3(
1.0, 0.0, 0.0,
0.0, 1.0, 0.0,
-src0.x, -src0.y, 1.0
);
mat3 shift2 = mat3(
1.0, 0.0, 0.0,
0.0, 1.0, 0.0,
dst0.x, dst0.y, 1.0
);
// Compute complex division dest_vect / src_vect to determine rotation
vec2 complex_rot = complex_div(dst1 - dst0, src1 - src0);
mat3 rotate = mat3(
complex_rot.x, complex_rot.y, 0.0,
-complex_rot.y, complex_rot.x, 0.0,
0.0, 0.0, 1.0
);
return shift2 * rotate * shift1;
}
mat4 map_triangles(vec3 src0, vec3 src1, vec3 src2, vec3 dst0, vec3 dst1, vec3 dst2){
/*
Return an affine transform which maps the triangle (src0, src1, src2)
@ -179,36 +122,3 @@ mat4 get_xyz_to_uv(vec3 b0, vec3 b1, vec3 b2, float temp_is_linear, out float is
// return map_point_pairs(b0, b2, dst0, dst1);
return map_triangles(b0, b1, b2, dst0, dst1, dst2);
}
mat3 get_xy_to_uv(vec2 b0, vec2 b1, vec2 b2, float temp_is_linear, out float is_linear){
/*
Returns a matrix for an affine transformation which maps a set of quadratic
bezier controls points into a new coordinate system such that the bezier curve
coincides with y = x^2, or in the case of a linear curve, it's mapped to the x-axis.
*/
vec2 dst0;
vec2 dst1;
is_linear = temp_is_linear;
// Portions of the parabola y = x^2 where abs(x) exceeds
// this value are treated as straight lines.
float thresh = 2.0;
if (!bool(is_linear)){
vec2 xs = xs_on_clean_parabola(b0, b1, b2);
float x0 = xs.x;
float x2 = xs.y;
if((x0 > thresh && x2 > thresh) || (x0 < -thresh && x2 < -thresh)){
is_linear = 1.0;
}else{
dst0 = vec2(x0, x0 * x0);
dst1 = vec2(x2, x2 * x2);
}
}
// Check if is_linear status changed above
if (bool(is_linear)){
dst0 = vec2(0, 0);
dst1 = vec2(1, 0);
}
return map_point_pairs(b0, b2, dst0, dst1);
}