uniform isamplerBuffer bezier_id_buffer_texture;
layout(lines) in;
-layout(line_strip, max_vertices = 100) out;
+layout(line_strip, max_vertices = 101) out;
in int objectid[];
+in vec2 pixsize[];
+
+//TODO: I thought this might be useful, maybe not.
+float areatriangle(vec2 a, vec2 b, vec2 c)
+{
+ return (c.y-a.y)*(b.y-a.y) - (b.x - a.x)*(c.x-a.x);
+}
void main()
{
int bezierid = texelFetch(bezier_id_buffer_texture, objectid[0]).r;
vec2 boundssize = gl_in[1].gl_Position.xy - gl_in[0].gl_Position.xy;
- vec2 coeff0 = texelFetch(bezier_buffer_texture, bezierid*3).rg + gl_in[0].gl_Position.xy ;
- vec2 coeff1 = texelFetch(bezier_buffer_texture, bezierid*3+1).rg * boundssize + gl_in[0].gl_Position.xy;
- vec2 coeff2 = texelFetch(bezier_buffer_texture, bezierid*3+2).rg * boundssize + gl_in[0].gl_Position.xy;
- for (int i = 0; i <= 100; ++i)
+ vec2 coeff0 = texelFetch(bezier_buffer_texture, bezierid*4).rg;
+ vec2 coeff1 = texelFetch(bezier_buffer_texture, bezierid*4+1).rg;
+ vec2 coeff2 = texelFetch(bezier_buffer_texture, bezierid*4+2).rg;
+ vec2 coeff3 = texelFetch(bezier_buffer_texture, bezierid*4+3).rg;
+
+ vec2 boundspxsize = pixsize[0];
+ int blen = clamp(int(abs(boundspxsize.x)),2,100);
+ float invblen = 1.0f/float(blen);
+ for (int i = 0; i <= blen; ++i)
{
- float t = i * 0.01f;
+ float t = i * invblen;
float oneminust = 1.0f - t;
- float bernstein0 = t*t;
- float bernstein1 = 2*t*oneminust;
- float bernstein2 = oneminust*oneminust;
- gl_Position = vec4(coeff0*bernstein0 + coeff1*bernstein1 + coeff2*bernstein2, 0.0, 1.0);
+ float bernstein0 = t*t*t;
+ float bernstein1 = 3*t*t*oneminust;
+ float bernstein2 = 3*t*oneminust*oneminust;
+ float bernstein3 = oneminust*oneminust*oneminust;
+ gl_Position = vec4((coeff0*bernstein0 + coeff1*bernstein1 + coeff2*bernstein2 + coeff3*bernstein3) * boundssize + gl_in[0].gl_Position.xy, 0.0, 1.0);
EmitVertex();
}