Ray-caster: pass the sphere count as a uniform

In the process, start exploring array size limits of various kinds.
This commit is contained in:
Aaron Fenyes 2024-08-26 00:43:42 -07:00
parent c5fe725b1b
commit 85db7b9be0
2 changed files with 29 additions and 10 deletions

View File

@ -23,8 +23,10 @@ vecInv sphere(vec3 center, float radius) {
// --- uniforms ---
// construction
const int SPHERE_MAX = 256;
// construction. the SPHERE_MAX array size seems to affect frame rate a lot,
// even though we should only be using the first few elements of each array
const int SPHERE_MAX = 12;
uniform int sphere_cnt;
uniform vecInv sphere_list[SPHERE_MAX];
// view
@ -128,13 +130,11 @@ vec2 sphere_cast(vecInv v, vec3 dir) {
}
void main() {
const int sphere_cnt = 3;
vec2 scr = (2.*gl_FragCoord.xy - resolution) / shortdim;
vec3 dir = vec3(focal_slope * scr, -1.);
// initialize two spheres
vecInv sphere_list_internal [sphere_cnt];
vecInv sphere_list_internal [SPHERE_MAX];
if (use_test_construction) {
/* DEBUG */
// spheres 0 and 1 are identical in the test construction hard-coded
@ -149,14 +149,14 @@ void main() {
sphere_list_internal[i] = sphere_list[i];
}
}
vec3 color_list [sphere_cnt];
vec3 color_list [SPHERE_MAX];
color_list[0] = vec3(1., 0.25, 0.);
color_list[1] = vec3(0., 0.25, 1.);
color_list[2] = vec3(0.25, 0., 1.0);
// cast rays through the spheres
vec2 depth_pairs [sphere_cnt];
taggedFrag frags [2*sphere_cnt];
vec2 depth_pairs [SPHERE_MAX];
taggedFrag frags [2*SPHERE_MAX];
int frag_cnt = 0;
for (int i = 0; i < sphere_cnt; ++i) {
vec2 hit_depths = sphere_cast(sphere_list_internal[i], dir);

View File

@ -101,7 +101,7 @@ fn main() {
on_mount(move || {
// list construction elements
const SPHERE_MAX: usize = 256;
const SPHERE_MAX: usize = 12;
let mut sphere_vec = Vec::<DVector<f64>>::new();
// get the display canvas
@ -142,14 +142,32 @@ fn main() {
console::log_1(&JsValue::from(link_msg));
ctx.use_program(Some(&program));
/* DEBUG */
// print the maximum number of vectors that can be passed as
// uniforms to a fragment shader. the OpenGL ES 3.0 standard
// requires this maximum to be at least 224, as discussed in the
// documentation of the GL_MAX_FRAGMENT_UNIFORM_VECTORS parameter
// here:
//
// https://registry.khronos.org/OpenGL-Refpages/es3.0/html/glGet.xhtml
//
// there are also other size limits. for example, on Aaron's
// machine, the the length of a float or genType array seems to be
// capped at 1024 elements
console::log_2(
&ctx.get_parameter(WebGl2RenderingContext::MAX_FRAGMENT_UNIFORM_VECTORS).unwrap(),
&JsValue::from("uniform vectors available")
);
// find indices of vertex attributes and uniforms
let position_index = ctx.get_attrib_location(&program, "position") as u32;
let sphere_cnt_loc = ctx.get_uniform_location(&program, "sphere_cnt");
let sphere_sp_locs = get_uniform_array_locations::<SPHERE_MAX>(
&ctx, &program, "sphere_list", "sp"
);
let sphere_lt_locs = get_uniform_array_locations::<SPHERE_MAX>(
&ctx, &program, "sphere_list", "lt"
);
let position_index = ctx.get_attrib_location(&program, "position") as u32;
let resolution_loc = ctx.get_uniform_location(&program, "resolution");
let shortdim_loc = ctx.get_uniform_location(&program, "shortdim");
let ctrl_loc = ctx.get_uniform_location(&program, "ctrl"); /* DEBUG */
@ -192,6 +210,7 @@ fn main() {
ctx.uniform1f(shortdim_loc.as_ref(), width.min(height));
// pass the construction
ctx.uniform1i(sphere_cnt_loc.as_ref(), sphere_vec.len() as i32);
for n in 0..sphere_vec.len() {
let v = &sphere_vec[n];
ctx.uniform3f(