You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
491 lines
16 KiB
491 lines
16 KiB
|
|
// =========================================================================
|
|
// ======================== 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};
|
|
__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 = { 0.0f, 0.0f, 0.0f, 0.0f };
|
|
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);
|
|
}
|
|
|
|
float Distance(float3 a) {
|
|
return fast_length(a);
|
|
}
|
|
|
|
|
|
// Phong + diffuse lighting function for g
|
|
// 0 1 2 3 4 5 6 7 8 9
|
|
// {r, g, b, i, x, y, z, x', y', z'}
|
|
|
|
float4 view_light(float4 in_color, float3 light, float4 light_color, float3 view, int3 mask) {
|
|
|
|
if (all(light == zeroed_float3))
|
|
return zeroed_float4;
|
|
|
|
float d = Distance(light) / 280.0f;
|
|
d *= d;
|
|
|
|
float diffuse = max(dot(normalize(convert_float3(mask)), normalize(light)), 0.0f);
|
|
in_color += diffuse * light_color * 0.5f / d;
|
|
|
|
if (dot(light, normalize(convert_float3(mask))) > 0.0f)
|
|
{
|
|
// Small dots of light are caused by floating point error
|
|
// flipping bits on the face mask and screwing up this calculation
|
|
float3 halfwayVector = normalize(normalize(light) + normalize(view));
|
|
float specTmp = max(dot(normalize(convert_float3(mask)), halfwayVector), 0.0f);
|
|
in_color += pow(specTmp, 8.0f) * light_color * 0.5f / d;
|
|
}
|
|
if (in_color.w > 1.0f){
|
|
in_color.xyz *= in_color.w;
|
|
}
|
|
|
|
return in_color;
|
|
}
|
|
|
|
|
|
int rand(int* seed) // 1 <= *seed < m
|
|
{
|
|
int const a = 16807; //ie 7**5
|
|
int const m = 2147483647; //ie 2**31-1
|
|
|
|
*seed = ((*seed) * a) % m;
|
|
return(*seed);
|
|
}
|
|
|
|
// =========================================================================
|
|
// ========================= OCTREE TRAVERSAL ==============================
|
|
|
|
bool get_oct_vox(
|
|
int3 position,
|
|
global ulong *octree_descriptor_buffer,
|
|
global uint *octree_attachment_lookup_buffer,
|
|
global ulong *octree_attachment_buffer,
|
|
global ulong *settings_buffer
|
|
){
|
|
|
|
// push the root node to the parent stack
|
|
ulong current_index = *settings_buffer;
|
|
ulong head = octree_descriptor_buffer[current_index];
|
|
|
|
uint parent_stack_position = 0;
|
|
ulong parent_stack[32];
|
|
|
|
uchar scale = 0;
|
|
uchar idx_stack[32];
|
|
|
|
ulong current_descriptor = 0;
|
|
|
|
bool found = false;
|
|
|
|
parent_stack[parent_stack_position] = head;
|
|
|
|
// Set our initial dimension and the position at the corner of the oct to keep track of our position
|
|
int dimension = 64;
|
|
int3 quad_position = zeroed_int3;
|
|
|
|
// While we are not at the required resolution
|
|
// Traverse down by setting the valid/leaf mask to the subvoxel
|
|
// Check to see if it is valid
|
|
// Yes?
|
|
// Check to see if it is a leaf
|
|
// No? Break
|
|
// Yes? Scale down to the next hierarchy, push the parent to the stack
|
|
//
|
|
// No?
|
|
// Break
|
|
while (dimension > 1) {
|
|
|
|
// So we can be a little bit tricky here and increment our
|
|
// array index that holds our masks as we build the idx.
|
|
// Adding 1 for X, 2 for Y, and 4 for Z
|
|
int mask_index = 0;
|
|
|
|
// Do the logic steps to find which sub oct we step down into
|
|
if (position.x >= (dimension / 2) + quad_position.x) {
|
|
|
|
// Set our voxel position to the (0,0) of the correct oct
|
|
quad_position.x += (dimension / 2);
|
|
|
|
// increment the mask index and mentioned above
|
|
mask_index += 1;
|
|
|
|
// Set the idx to represent the move
|
|
idx_stack[scale] |= idx_set_x_mask;
|
|
|
|
}
|
|
if (position.y >= (dimension / 2) + quad_position.y) {
|
|
|
|
quad_position.y |= (dimension / 2);
|
|
mask_index += 2;
|
|
idx_stack[scale] |= idx_set_y_mask;
|
|
|
|
}
|
|
if (position.z >= (dimension / 2) + quad_position.z) {
|
|
|
|
quad_position.z += (dimension / 2);
|
|
mask_index += 4;
|
|
idx_stack[scale] |= idx_set_z_mask;
|
|
}
|
|
|
|
// Check to see if we are on a valid oct
|
|
if ((head >> 16) & mask_8[mask_index]) {
|
|
|
|
// Check to see if it is a leaf
|
|
if ((head >> 24) & mask_8[mask_index]) {
|
|
|
|
// If it is, then we cannot traverse further as CP's won't have been generated
|
|
found = true;
|
|
return found;
|
|
}
|
|
|
|
// If all went well and we found a valid non-leaf oct then we will traverse further down the hierarchy
|
|
scale++;
|
|
dimension /= 2;
|
|
|
|
// Count the number of valid octs that come before and add it to the index to get the position
|
|
// Negate it by one as it counts itself
|
|
int count = popcount((uchar)(head >> 16) & count_mask_8[mask_index]) - 1;
|
|
|
|
// access the element at which head points to and then add the specified number of indices
|
|
// to get to the correct child descriptor
|
|
current_index = current_index + (head & child_pointer_mask) + count;
|
|
head = octree_descriptor_buffer[current_index];
|
|
|
|
// Increment the parent stack position and put the new oct node as the parent
|
|
parent_stack_position++;
|
|
parent_stack[parent_stack_position] = head;
|
|
|
|
}
|
|
else {
|
|
// If the oct was not valid, then no CP's exists any further
|
|
// This implicitly says that if it's non-valid then it must be a leaf!!
|
|
|
|
// It appears that the traversal is now working but I need
|
|
// to focus on how to now take care of the end condition.
|
|
// Currently it adds the last parent on the second to lowest
|
|
// oct CP. Not sure if thats correct
|
|
found = 0;
|
|
return found;
|
|
}
|
|
}
|
|
|
|
found = 1;
|
|
return found;
|
|
}
|
|
|
|
// =========================================================================
|
|
// ========================= RAYCASTER ENTRY ===============================
|
|
|
|
__kernel void raycaster(
|
|
global char* map,
|
|
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,
|
|
__read_only image2d_t texture_atlas,
|
|
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
|
|
){
|
|
|
|
// 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));
|
|
float3 ray_dir = projection_matrix[pixel.x + (*resolution).x * pixel.y];
|
|
|
|
// Pitch
|
|
ray_dir = (float3)(
|
|
ray_dir.z * sin((*cam_dir).x) + ray_dir.x * cos((*cam_dir).x),
|
|
ray_dir.y,
|
|
ray_dir.z * cos((*cam_dir).x) - ray_dir.x * sin((*cam_dir).x)
|
|
);
|
|
|
|
// Yaw
|
|
ray_dir = (float3)(
|
|
ray_dir.x * cos((*cam_dir).y) - ray_dir.y * sin((*cam_dir).y),
|
|
ray_dir.x * sin((*cam_dir).y) + ray_dir.y * cos((*cam_dir).y),
|
|
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};
|
|
voxel_step *= (ray_dir > 0) - (ray_dir < 0);
|
|
|
|
// Setup the voxel coords from the camera origin
|
|
int3 voxel = convert_int3(*cam_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);
|
|
|
|
// Intersection T is the collection of the next intersection points
|
|
// for all 3 axis XYZ. We take the full positive cardinality when
|
|
// subtracting the floor, so we must transfer the sign over from
|
|
// the voxel step
|
|
float3 intersection_t = delta_t * ((*cam_pos) - ceil(*cam_pos)) * convert_float3(voxel_step);
|
|
|
|
// When we transfer the sign over, we get the correct direction of
|
|
// the offset, but we merely transposed over the value instead of mirroring
|
|
// it over the axis like we want. So here, isless returns a boolean if intersection_t
|
|
// is less than 0 which dictates whether or not we subtract the delta which in effect
|
|
// mirrors the offset
|
|
intersection_t -= delta_t * convert_float3(isless(intersection_t, 0));
|
|
|
|
int distance_traveled = 0;
|
|
int max_distance = 700;
|
|
uint bounce_count = 0;
|
|
int3 face_mask = { 0, 0, 0 };
|
|
int voxel_data = 0;
|
|
float3 face_position = zeroed_float3;
|
|
float4 voxel_color= zeroed_float4;
|
|
float2 tile_face_position = zeroed_float2;
|
|
float3 sign = zeroed_float3;
|
|
float4 color_accumulator = zeroed_float4;
|
|
float fog_distance = 0.0f;
|
|
|
|
bool shadow_ray = false;
|
|
|
|
// Andrew Woo's raycasting algo
|
|
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);
|
|
intersection_t += delta_t * fabs(convert_float3(face_mask.xyz));
|
|
voxel.xyz += voxel_step.xyz * face_mask.xyz;
|
|
|
|
// Test for out of bounds contions, add fog
|
|
if (any(voxel >= *map_dim) || any(voxel < 0)){
|
|
voxel.xyz -= voxel_step.xyz * face_mask.xyz;
|
|
color_accumulator = mix(fog_color, voxel_color, 1.0f - max(distance_traveled / 700.0f, 0.0f));
|
|
color_accumulator.w *= 4;
|
|
break;
|
|
}
|
|
|
|
// If we hit a voxel
|
|
if (voxel.x < 64 && voxel.y < 64 && voxel.z < 64){
|
|
if (get_oct_vox(
|
|
voxel,
|
|
octree_descriptor_buffer,
|
|
octree_attachment_lookup_buffer,
|
|
octree_attachment_buffer,
|
|
settings_buffer
|
|
)){
|
|
voxel_data = 5;
|
|
} else {
|
|
voxel_data = 0;
|
|
}
|
|
} else {
|
|
voxel_data = map[voxel.x + (*map_dim).x * (voxel.y + (*map_dim).z * (voxel.z))];
|
|
}
|
|
|
|
|
|
if (voxel_data != 0) {
|
|
|
|
// Determine where on the 2d plane the ray intersected
|
|
face_position = zeroed_float3;
|
|
tile_face_position = zeroed_float2;
|
|
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
|
|
if (face_mask.x == -1) {
|
|
|
|
sign.x *= -1.0;
|
|
|
|
// the next intersection for this plane - the last intersection of the passed plane / delta of this plane
|
|
// basically finds how far in on the other 2 axis we are when the ray traversed the plane
|
|
float z_percent = (intersection_t.z - (intersection_t.x - delta_t.x)) / delta_t.z;
|
|
float y_percent = (intersection_t.y - (intersection_t.x - delta_t.x)) / delta_t.y;
|
|
|
|
// Since we intersected face x, we know that we are at the face (1.0)
|
|
// 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 = 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 = face_position.xz;
|
|
}
|
|
|
|
else if (face_mask.z == -1) {
|
|
|
|
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 = face_position.xy;
|
|
|
|
}
|
|
|
|
// Because the raycasting process is agnostic to the quadrant
|
|
// it's working in, we need to transpose the sign over to the face positions.
|
|
// If we don't it will think that it is always working in the (1, 1, 1) quadrant
|
|
// 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((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;
|
|
} else {
|
|
tile_face_position.x = 1.0 - tile_face_position.x;
|
|
|
|
// 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 = 1.0f - tile_face_position.x;
|
|
tile_face_position.y = 1.0f - tile_face_position.y;
|
|
}
|
|
}
|
|
|
|
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
|
|
|
|
// TEXTURE HIT + SHADOW REDIRECTION
|
|
if (voxel_data == 5 && !shadow_ray){
|
|
|
|
shadow_ray = true;
|
|
voxel_color.xyz += (float3)read_imagef(
|
|
texture_atlas,
|
|
convert_int2(tile_face_position * convert_float2(*atlas_dim / *tile_dim)) +
|
|
convert_int2((float2)(3, 0) * convert_float2(*atlas_dim / *tile_dim))
|
|
).xyz/2;
|
|
|
|
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]),
|
|
(convert_float3(voxel) + face_position) - (*cam_pos),
|
|
face_mask * voxel_step
|
|
);
|
|
|
|
fog_distance = distance_traveled;
|
|
max_distance = distance_traveled + DistanceBetweenPoints(convert_float3(voxel), (float3)(lights[4], lights[5], lights[6]));
|
|
|
|
|
|
float3 hit_pos = convert_float3(voxel) + face_position;
|
|
ray_dir = normalize((float3)(lights[4], lights[5], lights[6]) - hit_pos);
|
|
if (any(ray_dir == zeroed_float3))
|
|
return;
|
|
|
|
voxel -= voxel_step * face_mask;
|
|
voxel_step = ( 1, 1, 1 ) * ((ray_dir > 0) - (ray_dir < 0));
|
|
|
|
delta_t = fabs(1.0f / ray_dir);
|
|
intersection_t = delta_t * ((hit_pos)-floor(hit_pos)) * convert_float3(voxel_step);
|
|
intersection_t += delta_t * -convert_float3(isless(intersection_t, 0));
|
|
|
|
// REFLECTION
|
|
} else if (voxel_data == 6 && !shadow_ray) {
|
|
|
|
voxel_color.xyz += (float3)read_imagef(
|
|
texture_atlas,
|
|
convert_int2(tile_face_position * convert_float2(*atlas_dim / *tile_dim)) +
|
|
convert_int2((float2)(3, 4) * convert_float2(*atlas_dim / *tile_dim))
|
|
).xyz/4;
|
|
|
|
voxel_color.w -= 0.0f;
|
|
//max_distance += 200;
|
|
|
|
|
|
float3 hit_pos = convert_float3(voxel) + face_position;
|
|
ray_dir *= sign;
|
|
if (any(ray_dir == zeroed_float3))
|
|
return;
|
|
|
|
voxel -= voxel_step * face_mask;
|
|
voxel_step = ( 1, 1, 1 );
|
|
voxel_step *= (ray_dir > 0) - (ray_dir < 0);
|
|
|
|
//voxel = convert_int3(hit_pos);
|
|
|
|
delta_t = fabs(1.0f / ray_dir);
|
|
intersection_t = delta_t * ((hit_pos)-floor(hit_pos)) * convert_float3(voxel_step);
|
|
intersection_t += delta_t * -convert_float3(isless(intersection_t, 0));
|
|
|
|
bounce_count += 1;
|
|
|
|
// SHADOW RAY HIT
|
|
} else {
|
|
color_accumulator = 0;
|
|
break;
|
|
}
|
|
}
|
|
|
|
// At the bottom of the while loop, add one to the distance ticker
|
|
distance_traveled++;
|
|
}
|
|
color_accumulator = mix(fog_color, color_accumulator, 1.0f - max(fog_distance / 700.0f, 0.0f));
|
|
write_imagef(
|
|
image,
|
|
pixel,
|
|
color_accumulator
|
|
);
|
|
|
|
return;
|
|
}
|