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voxel-raycaster
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More optimizing, removing some dumb casts. Some are needed though when they really shouldn't be? Also somehow broke shadowing in the last few commits and never noticed D=

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master
MitchellHansen 7 years ago
parent c5c65474d6
commit ed99716565
1 changed files with 75 additions and 163 deletions
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236
kernels/ray_caster_kernel.cl
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@ -1,4 +1,7 @@
// =========================================================================
// ======================== INITIALIZER CONSTANTS ==========================
__constant float4 zeroed_float4 = {0.0f, 0.0f, 0.0f, 0.0f};
__constant float3 zeroed_float3 = {0.0f, 0.0f, 0.0f};
__constant float2 zeroed_float2 = {0.0f, 0.0f};
@ -6,31 +9,54 @@ __constant int4 zeroed_int4 = {0, 0, 0, 0};
__constant int3 zeroed_int3 = {0, 0, 0};
__constant int2 zeroed_int2 = {0, 0};
// =========================================================================
// ============================ OCTREE CONSTANTS ===========================
// (X, Y, Z) mask for the idx
__constant const uchar idx_set_x_mask = 0x1;
__constant const uchar idx_set_y_mask = 0x2;
__constant const uchar idx_set_z_mask = 0x4;
__constant const uchar mask_8[8] = {
0x1, 0x2, 0x4, 0x8,
0x10, 0x20, 0x40, 0x80
};
// Mask for counting the previous valid bits
__constant const uchar count_mask_8[8] = {
0x1, 0x3, 0x7, 0xF,
0x1F, 0x3F, 0x7F, 0xFF
};
// uint64_t manipulation masks
__constant const ulong child_pointer_mask = 0x0000000000007fff;
__constant const ulong far_bit_mask = 0x8000;
__constant const ulong valid_mask = 0xFF0000;
__constant const ulong leaf_mask = 0xFF000000;
__constant const ulong contour_pointer_mask = 0xFFFFFF00000000;
__constant const ulong contour_mask = 0xFF00000000000000;
// =========================================================================
// ========================= RAYCASTER CONSTANTS ===========================
constant float4 fog_color = { 0.73f, 0.81f, 0.89f, 0.8f };
constant float4 overshoot_color = { 0.00f, 0.00f, 0.00f, 0.00f };
constant float4 overshoot_color_2 = { 0.00f, 0.00f, 0.00f, 0.00f };
// =========================================================================
// =========================================================================
// =========================================================================
// ========================= HELPER FUNCTIONS ==============================
float DistanceBetweenPoints(float3 a, float3 b) {
return fast_distance(a, b);
//return sqrt(pow(a.x - b.x, 2) + pow(a.y - b.y, 2) + pow(a.z - b.z, 2));
}
float Distance(float3 a) {
return fast_length(a);
//return sqrt(pow(a.x, 2) + pow(a.y, 2) + pow(a.z, 2));
}
// Naive incident ray light
float4 white_light(float4 input, float3 light, int3 mask) {
input.w = input.w + acos(
dot(
normalize(light),
normalize(convert_float3(mask * (-mask)))
)
) / 32;
input.w += 0.25f;
return input;
}
// Phong + diffuse lighting function for g
// 0 1 2 3 4 5 6 7 8 9
@ -72,29 +98,8 @@ int rand(int* seed) // 1 <= *seed < m
return(*seed);
}
// (X, Y, Z) mask for the idx
__constant const uchar idx_set_x_mask = 0x1;
__constant const uchar idx_set_y_mask = 0x2;
__constant const uchar idx_set_z_mask = 0x4;
__constant const uchar mask_8[8] = {
0x1, 0x2, 0x4, 0x8,
0x10, 0x20, 0x40, 0x80
};
// Mask for counting the previous valid bits
__constant const uchar count_mask_8[8] = {
0x1, 0x3, 0x7, 0xF,
0x1F, 0x3F, 0x7F, 0xFF
};
// uint64_t manipulation masks
__constant const ulong child_pointer_mask = 0x0000000000007fff;
__constant const ulong far_bit_mask = 0x8000;
__constant const ulong valid_mask = 0xFF0000;
__constant const ulong leaf_mask = 0xFF000000;
__constant const ulong contour_pointer_mask = 0xFFFFFF00000000;
__constant const ulong contour_mask = 0xFF00000000000000;
// =========================================================================
// ========================= OCTREE TRAVERSAL ==============================
bool get_oct_vox(
int3 position,
@ -223,106 +228,27 @@ bool get_oct_vox(
return found;
}
// =================================== Boolean ray intersection ============================
// =========================================================================================
bool cast_light_intersection_ray(
global char* map,
global int3* map_dim,
float3 ray_dir,
float3 ray_pos,
global float* lights,
global int* light_count
){
float distance_to_light = DistanceBetweenPoints(ray_pos, (float3)(lights[4], lights[5], lights[6]));
//if (distance_to_light > 200.0f){
// return false;
//}
// Setup the voxel step based on what direction the ray is pointing
int3 voxel_step = { 1, 1, 1 };
voxel_step *= (ray_dir > 0) - (ray_dir < 0);
if (any(ray_dir == zeroed_float3))
return false;
// Setup the voxel coords from the camera origin
int3 voxel = convert_int3(ray_pos);
// Delta T is the units a ray must travel along an axis in order to traverse an integer split
float3 delta_t = fabs(1.0f / ray_dir);
// Compute intersection_t and add in the offset
float3 intersection_t = delta_t * ((ray_pos)-floor(ray_pos)) * convert_float3(voxel_step);
// for negative values, wrap around the delta_t
intersection_t += delta_t * -convert_float3(isless(intersection_t, 0));
int3 face_mask =zeroed_int3;
int length_cutoff = 0;
// Andrew Woo's raycasting algo
do {
// Fancy no branch version of the logic step
face_mask = intersection_t.xyz <= min(intersection_t.yzx, intersection_t.zxy);
intersection_t += delta_t * fabs(convert_float3(face_mask.xyz));
voxel.xyz += voxel_step.xyz * face_mask.xyz;
if (any(voxel >= *map_dim) ||
any(voxel < 0)) {
return false;
}
// If we hit a voxel
int voxel_data = map[voxel.x + (*map_dim).x * (voxel.y + (*map_dim).z * (voxel.z))];
if (voxel_data != 0)
return true;
if (++length_cutoff > 300)
return false;
} while (any(isless(intersection_t, (float3)(distance_to_light - 1))));
return false;
}
// ====================================== Raycaster entry point =====================================
// ==================================================================================================
constant float4 fog_color = { 0.73f, 0.81f, 0.89f, 0.8f };
constant float4 overshoot_color = { 0.00f, 0.00f, 0.00f, 0.00f };
constant float4 overshoot_color_2 = { 0.00f, 0.00f, 0.00f, 0.00f };
// =========================================================================
// ========================= RAYCASTER ENTRY ===============================
__kernel void raycaster(
global char* map,
global int3* map_dim,
global int2* resolution,
constant int3* map_dim,
constant int2* resolution,
global float3* projection_matrix,
global float2* cam_dir,
global float3* cam_pos,
global float* lights,
global int* light_count,
__write_only image2d_t image,
//global int* seed_memory,
__read_only image2d_t texture_atlas,
global int2 *atlas_dim,
global int2 *tile_dim,
constant int2 *atlas_dim,
constant int2 *tile_dim,
global ulong *octree_descriptor_buffer,
global uint *octree_attachment_lookup_buffer,
global ulong *octree_attachment_buffer,
global ulong *settings_buffer
){
// int global_id = x * y;
// Get and set the random seed from seed memory
//int seed = seed_memory[global_id];
//int random_number = rand(&seed);
//seed_memory[global_id] = seed;
// Get the pixel on the viewport, and find the view matrix ray that matches it
int2 pixel = (int2)(get_global_id(0), get_global_id(1));
@ -342,6 +268,8 @@ __kernel void raycaster(
ray_dir.z
);
if (any(ray_dir == zeroed_float3))
return;
// Setup the voxel step based on what direction the ray is pointing
int3 voxel_step = {1, 1, 1};
@ -352,8 +280,6 @@ __kernel void raycaster(
// Delta T is the units a ray must travel along an axis in order to
// traverse an integer split
if (any(ray_dir == zeroed_float3))
return;
float3 delta_t = fabs(1.0f / ray_dir);
// Intersection T is the collection of the next intersection points
@ -378,12 +304,12 @@ __kernel void raycaster(
float4 voxel_color= zeroed_float4;
float2 tile_face_position = zeroed_float2;
float3 sign = zeroed_float3;
float4 first_strike = zeroed_float4;
float4 color_accumulator = zeroed_float4;
bool shadow_ray = false;
// Andrew Woo's raycasting algo
while (distance_traveled < max_distance && bounce_count < 2) {
while (distance_traveled < max_distance && bounce_count < 4) {
// Fancy no branch version of the logic step
face_mask = intersection_t.xyz <= min(intersection_t.yzx, intersection_t.zxy);
@ -392,13 +318,11 @@ __kernel void raycaster(
// Test for out of bounds contions, add fog
if (any(voxel >= *map_dim) || any(voxel < 0)){
voxel_data = 5;
voxel.xyz -= voxel_step.xyz * face_mask.xyz;
first_strike = mix(fog_color, voxel_color, 1.0f - max(distance_traveled / 700.0f, 0.0f));
color_accumulator = mix(fog_color, voxel_color, 1.0f - max(distance_traveled / 700.0f, 0.0f));
break;
}
// If we hit a voxel
if (voxel.x < 64 && voxel.y < 64 && voxel.z < 64){
if (get_oct_vox(
@ -419,11 +343,10 @@ __kernel void raycaster(
if (voxel_data != 0) {
// Determine where on the 2d plane the ray intersected
face_position = zeroed_float3;
tile_face_position = zeroed_float2;
sign = (float3)(1.0f, 1.0f, 1.0f);
sign = (1.0f, 1.0f, 1.0f);
// First determine the percent of the way the ray is towards the next intersection_t
// in relation to the xyz position on the plane
@ -440,16 +363,15 @@ __kernel void raycaster(
// I think the 1.001f rendering bug is the ray thinking it's within the voxel
// even though it's sitting on the very edge
face_position = (float3)(1.0001f, y_percent, z_percent);
tile_face_position = (float2)(y_percent, z_percent);
tile_face_position = face_position.yz;
}
else if (face_mask.y == -1) {
sign.y *= -1.0;
float x_percent = (intersection_t.x - (intersection_t.y - delta_t.y)) / delta_t.x;
float z_percent = (intersection_t.z - (intersection_t.y - delta_t.y)) / delta_t.z;
face_position = (float3)(x_percent, 1.0001f, z_percent);
tile_face_position = (float2)(x_percent, z_percent);
tile_face_position = face_position.xz;
}
else if (face_mask.z == -1) {
@ -457,9 +379,8 @@ __kernel void raycaster(
sign.z *= -1.0;
float x_percent = (intersection_t.x - (intersection_t.z - delta_t.z)) / delta_t.x;
float y_percent = (intersection_t.y - (intersection_t.z - delta_t.z)) / delta_t.y;
face_position = (float3)(x_percent, y_percent, 1.0001f);
tile_face_position = (float2)(x_percent, y_percent);
tile_face_position = face_position.xy;
}
@ -469,8 +390,8 @@ __kernel void raycaster(
// and will just "copy" the quadrant. This includes shadows as they use the face_position
// in order to cast the intersection ray!!
face_position.x = select((float)(face_position.x), (float)(-face_position.x + 1.0f), (int)(ray_dir.x > 0));
tile_face_position.x = select((float)(tile_face_position.x), (float)(-tile_face_position.x + 1.0f), (int)(ray_dir.x < 0));
face_position.x = select((face_position.x), (-face_position.x + 1.0f), (int)(ray_dir.x > 0));
tile_face_position.x = select((tile_face_position.x), (-tile_face_position.x + 1.0f), (int)(ray_dir.x < 0));
if (ray_dir.y > 0){
face_position.y = -face_position.y + 1;
@ -480,25 +401,16 @@ __kernel void raycaster(
// We run into the Hairy ball problem, so we need to define
// a special case for the zmask
if (face_mask.z == -1) {
tile_face_position.x = 1.0 - tile_face_position.x;
tile_face_position.y = 1.0 - tile_face_position.y;
tile_face_position.x = 1.0f - tile_face_position.x;
tile_face_position.y = 1.0f - tile_face_position.y;
}
}
face_position.z = select((float)(face_position.z), (float)(-face_position.z + 1.0f), (int)(ray_dir.z > 0));
tile_face_position.y = select((float)(tile_face_position.y), (float)(-tile_face_position.y + 1.0f), (int)(ray_dir.z < 0));
// Now either use the face position to retrieve a texture sample, or
// just a plain color for the voxel color. Notice the JANK -1 after the
// conditionals in the select statement. That's because select works on negs
// and pos's. So a false equality will still eval as true as it is technically
// a positive result (0)
// voxel_color = select(
// (float4)(0.25f, 0.64f, 0.87f, 0.0f),
// (float4)voxel_color,
// (int4)((voxel_data == 5) - 1)
// );
face_position.z = select((face_position.z), (-face_position.z + 1.0f), (int)(ray_dir.z > 0));
tile_face_position.y = select((tile_face_position.y), (-tile_face_position.y + 1.0f), (int)(ray_dir.z < 0));
// Now we detect what type of of voxel we intersected and decide whether
// to bend the ray, send out a light intersection ray, or add texture color
// SHADOWING
if (voxel_data == 5 && !shadow_ray){
@ -510,8 +422,7 @@ __kernel void raycaster(
convert_int2((float2)(3, 0) * convert_float2(*atlas_dim / *tile_dim))
).xyz/2;
//voxel_color.w = 0.0f;
first_strike = view_light(
color_accumulator = view_light(
voxel_color,
(convert_float3(voxel) + face_position) - (float3)(lights[4], lights[5], lights[6]),
(float4)(lights[0], lights[1], lights[2], lights[3]),
@ -570,16 +481,17 @@ __kernel void raycaster(
// SHADOW RAY HIT
} else {
max_distance = 0;
distance_traveled = 1;
break;
}
}
// At the bottom of the while loop, add one to the distance ticker
distance_traveled++;
}
write_imagef(
image,
pixel,
first_strike
color_accumulator
);
return;

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