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Change fill shaders to compute orientation inside

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This commit is contained in:
Grant Sanderson 2020-02-07 09:31:57 -08:00
parent db0029c32b
commit 9b3d294464
2 changed files with 32 additions and 18 deletions
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39
manimlib/shaders/quadratic_bezier_fill_geom.glsl
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@ -9,7 +9,8 @@ uniform float anti_alias_width;
in vec2 bp[3];
in vec4 v_color[3];
in float v_fill_type[3];
in float v_fill_all[3];
in float v_orientation[3];
out vec4 color;
out float fill_type;
@ -75,7 +76,7 @@ void emit_simple_triangle(){
}
void emit_pentagon(vec2 bp0, vec2 bp1, vec2 bp2, float in_or_out){
void emit_pentagon(vec2 bp0, vec2 bp1, vec2 bp2, float orientation){
// Tangent vectors
vec2 t01 = normalize(bp1 - bp0);
vec2 t12 = normalize(bp2 - bp1);
@ -85,14 +86,22 @@ void emit_pentagon(vec2 bp0, vec2 bp1, vec2 bp2, float in_or_out){
// Inside and right turn -> rot left -> +1
// Outside and right turn -> rot right -> -1
float c_orient = (cross(t01, t12) > 0) ? 1 : -1;
float orient = in_or_out * c_orient;
c_orient *= orientation;
bool fill_in = (c_orient > 0);
fill_type = fill_in ? FILL_INSIDE : FILL_OUTSIDE;
// float orient = in_or_out * c_orient;
// Normal vectors
vec2 n01 = -orient * vec2(-t01.y, t01.x);
vec2 n12 = -orient * vec2(-t12.y, t12.x);
// Rotate tangent vector 90-degrees clockwise
// if the curve is positively oriented, otherwise
// rotate it 90-degrees counterclockwise
vec2 n01 = orientation * vec2(t01.y, -t01.x);
vec2 n12 = orientation * vec2(t12.y, -t12.x);
float aaw = 1 * anti_alias_width;
vec2 nudge1 = (fill_type == FILL_OUTSIDE) ? vec2(0) : 0.5 * aaw * (n01 + n12);
float aaw = anti_alias_width;
vec2 nudge1 = fill_in ? 0.5 * aaw * (n01 + n12) : vec2(0);
vec2 corners[5] = vec2[5](
bp0 + aaw * n01,
bp0,
@ -102,7 +111,7 @@ void emit_pentagon(vec2 bp0, vec2 bp1, vec2 bp2, float in_or_out){
);
int coords_index_map[5] = int[5](0, 1, 2, 3, 4);
if(in_or_out < 0) coords_index_map = int[5](1, 0, 2, 4, 3);
if(!fill_in) coords_index_map = int[5](1, 0, 2, 4, 3);
mat3 xy_to_uv = get_xy_to_uv(bp0, bp1);
mat3 xy_to_wz = get_xy_to_wz(bp0, bp1, bp2);
@ -115,10 +124,9 @@ void emit_pentagon(vec2 bp0, vec2 bp1, vec2 bp2, float in_or_out){
wz_coords = (xy_to_wz * vec3(corner, 1)).xy;
// I haven't a clue why an index map doesn't work just
// as well here, but for some reason it doesn't.
if(i < 2) color = v_color[0];
if(i < 2) color = v_color[0];
else if(i == 2) color = v_color[1];
else color = v_color[2];
// color = v_color[1];
else color = v_color[2];
set_gl_Position(corner);
EmitVertex();
}
@ -127,14 +135,16 @@ void emit_pentagon(vec2 bp0, vec2 bp1, vec2 bp2, float in_or_out){
void main(){
fill_type = v_fill_type[0];
float fill_all = v_fill_all[0];
if(fill_type == FILL_ALL){
if(fill_all == 1){
fill_type = FILL_ALL;
emit_simple_triangle();
}else{
vec2 new_bp[3];
int n = get_reduced_control_points(bp[0], bp[1], bp[2], new_bp);
bezier_degree = float(n);
float orientation = v_orientation[0];
vec2 bp0, bp1, bp2;
if(n == 0){
@ -150,8 +160,7 @@ void main(){
bp2 = new_bp[2];
}
float orient = (fill_type == FILL_INSIDE) ? 1 : -1;
emit_pentagon(bp0, bp1, bp2, orient);
emit_pentagon(bp0, bp1, bp2, orientation);
}
}

11
manimlib/shaders/quadratic_bezier_fill_vert.glsl
View file

@ -2,15 +2,20 @@
in vec3 point;
in vec4 color;
in float fill_type;
// fill_all is 0 or 1
in float fill_all;
// orientation is +1 for counterclockwise curves, -1 otherwise
in float orientation;
out vec2 bp; // Bezier control point
out vec4 v_color;
out float v_fill_type;
out float v_fill_all;
out float v_orientation;
void main(){
bp = point.xy; // TODO
v_color = color;
v_fill_type = fill_type;
v_fill_all = fill_all;
v_orientation = orientation;
}