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Fix unit normal issue with bezier fill

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This commit is contained in:
Grant Sanderson 2023-01-14 08:00:21 -08:00
parent c8238f6b39
commit 19a7721661
1 changed files with 21 additions and 19 deletions
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40
manimlib/shaders/quadratic_bezier_fill/geom.glsl
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@ -20,8 +20,6 @@ out float orientation;
out vec2 uv_coords;
out float is_linear;
vec3 unit_normal;
const float ANGLE_THRESHOLD = 1e-3;
@ -31,7 +29,7 @@ const float ANGLE_THRESHOLD = 1e-3;
#INSERT finalize_color.glsl
void emit_vertex_wrapper(vec3 point, int index){
void emit_vertex_wrapper(vec3 point, int index, vec3 unit_normal){
color = finalize_color(
v_color[index],
point,
@ -47,9 +45,9 @@ void emit_vertex_wrapper(vec3 point, int index){
}
void emit_simple_triangle(){
void emit_simple_triangle(vec3 unit_normal){
for(int i = 0; i < 3; i++){
emit_vertex_wrapper(verts[i], i);
emit_vertex_wrapper(verts[i], i, unit_normal);
}
EndPrimitive();
}
@ -63,13 +61,12 @@ void emit_pentagon(
// Unit tangent vector
vec3 t01,
vec3 t12,
// Unit normal
vec3 normal
vec3 unit_normal
){
// Vectors perpendicular to the curve in the plane of the curve
// pointing outside the curve
vec3 p0_perp = cross(t01, normal);
vec3 p2_perp = cross(t12, normal);
vec3 p0_perp = cross(t01, unit_normal);
vec3 p2_perp = cross(t12, unit_normal);
float angle = acos(clamp(dot(t01, t12), -1, 1));
is_linear = float(angle < ANGLE_THRESHOLD);
@ -98,7 +95,7 @@ void emit_pentagon(
int j = int(sign(i - 1) + 1); // Maps i = [0, 1, 2, 3, 4] onto j = [0, 0, 1, 2, 2]
vec3 corner = corners[i];
uv_coords = (xy_to_uv * vec3(corner.xy, 1.0)).xy;
emit_vertex_wrapper(corner, j);
emit_vertex_wrapper(corner, j, unit_normal);
}
EndPrimitive();
}
@ -111,19 +108,24 @@ void main(){
(v_vert_index[2] - v_vert_index[1]) != 1.0
);
if(bool(fill_all)){
emit_simple_triangle();
return;
}
vec3 p0 = verts[0];
vec3 p1 = verts[1];
vec3 p2 = verts[2];
vec3 t01 = normalize(p1 - p0);
vec3 t12 = normalize(p2 - p1);
unit_normal = normalize(cross(t01, t12));
vec3 t01 = p1 - p0;
vec3 t12 = p2 - p1;
vec3 unit_normal = normalize(cross(t01, t12));
if(bool(fill_all)){
emit_simple_triangle(unit_normal);
return;
}
orientation = v_orientation[1];
emit_pentagon(p0, p1, p2, t01, t12, unit_normal);
emit_pentagon(
p0, p1, p2,
normalize(t01),
normalize(t12),
unit_normal
);
}