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.
635 lines
24 KiB
635 lines
24 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 uchar3 idx_set_mask = {0x1, 0x2, 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 ==============================
|
|
|
|
// 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 = fast_length(light) * 0.01f;
|
|
d *= d;
|
|
|
|
float diffuse = max(dot(normalize(convert_float3(mask)), normalize(light)), 0.1f);
|
|
float specular = 0.0f;
|
|
|
|
if (diffuse > 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);
|
|
specular = pow(specTmp, 1.0f);
|
|
}
|
|
|
|
in_color += diffuse * light_color + specular * light_color / d;
|
|
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 ==============================
|
|
|
|
struct TraversalState {
|
|
|
|
int parent_stack_position;
|
|
ulong parent_stack[10];
|
|
ulong parent_stack_index[10];
|
|
|
|
uchar scale;
|
|
uchar idx_stack[10];
|
|
|
|
ulong current_descriptor;
|
|
ulong current_descriptor_index;
|
|
|
|
int3 oct_pos;
|
|
|
|
// ====== DEBUG =======
|
|
char found;
|
|
|
|
};
|
|
|
|
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
|
|
){
|
|
|
|
struct TraversalState ts;
|
|
|
|
// push the root node to the parent stack
|
|
ts.current_descriptor_index = *settings_buffer;
|
|
ts.current_descriptor = octree_descriptor_buffer[ts.current_descriptor_index];
|
|
ts.scale = 0;
|
|
ts.found = false;
|
|
ts.parent_stack[ts.scale] = ts.current_descriptor;
|
|
|
|
// Set our initial dimension and the position at the corner of the oct to keep track of our position
|
|
int dimension = OCTDIM;
|
|
ts.oct_pos = 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
|
|
ts.idx_stack[ts.scale] = 0;
|
|
|
|
// Do the logic steps to find which sub oct we step down into
|
|
if (position.x >= (dimension / 2) + ts.oct_pos.x) {
|
|
|
|
// Set our voxel position to the (0,0) of the correct oct
|
|
ts.oct_pos.x += (dimension / 2);
|
|
|
|
// Set the idx to represent the move
|
|
ts.idx_stack[ts.scale] |= idx_set_x_mask;
|
|
|
|
}
|
|
if (position.y >= (dimension / 2) + ts.oct_pos.y) {
|
|
|
|
ts.oct_pos.y += (dimension / 2);
|
|
ts.idx_stack[ts.scale] |= idx_set_y_mask;
|
|
|
|
}
|
|
if (position.z >= (dimension / 2) + ts.oct_pos.z) {
|
|
|
|
ts.oct_pos.z += (dimension / 2);
|
|
ts.idx_stack[ts.scale] |= idx_set_z_mask;
|
|
}
|
|
|
|
int mask_index = ts.idx_stack[ts.scale];
|
|
|
|
// Check to see if we are on a valid oct
|
|
if ((ts.current_descriptor >> 16) & mask_8[mask_index]) {
|
|
|
|
// Check to see if it is a leaf
|
|
if ((ts.current_descriptor >> 24) & mask_8[mask_index]) {
|
|
|
|
// If it is, then we cannot traverse further as CP's won't have been generated
|
|
ts.found = true;
|
|
return ts.found;
|
|
}
|
|
|
|
// If all went well and we found a valid non-leaf oct then we will traverse further down the hierarchy
|
|
ts.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)(ts.current_descriptor >> 16) & count_mask_8[mask_index]) - 1;
|
|
|
|
// access the far point at which the head points too. Determine it's value, and add
|
|
// a count of the valid bits to the index
|
|
if (far_bit_mask & octree_descriptor_buffer[ts.current_descriptor_index]) {
|
|
int far_pointer_index = ts.current_descriptor_index + (ts.current_descriptor & child_pointer_mask);
|
|
ts.current_descriptor_index = octree_descriptor_buffer[far_pointer_index] + count;
|
|
}
|
|
// access the element at which head points to and then add the specified number of indices
|
|
// to get to the correct child descriptor
|
|
else {
|
|
ts.current_descriptor_index = ts.current_descriptor_index + (ts.current_descriptor & child_pointer_mask) + count;
|
|
}
|
|
ts.current_descriptor = octree_descriptor_buffer[ts.current_descriptor_index];
|
|
|
|
|
|
ts.parent_stack[ts.scale] = ts.current_descriptor;
|
|
|
|
}
|
|
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
|
|
ts.found = 0;
|
|
return ts.found;
|
|
}
|
|
}
|
|
|
|
ts.found = 1;
|
|
return ts.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_rtn(*cam_pos);
|
|
|
|
//voxel = voxel + convert_int3(*cam_pos < 0.0f);
|
|
// 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 offset = delta_t * ((*cam_pos) - ceil(*cam_pos));
|
|
float3 intersection_t = offset* 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 < 2) {
|
|
|
|
// 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;
|
|
|
|
// =======================================================================================================================================
|
|
// =======================================================================================================================================
|
|
// =======================================================================================================================================
|
|
|
|
// uchar prev_val = traversal_state.idx_stack[traversal_state.scale];
|
|
// uint8_t this_face_mask = 0;
|
|
//
|
|
// // Check the voxel face that we traversed
|
|
// // and increment the idx in the idx stack
|
|
// if (face_mask.x) {
|
|
// this_face_mask = Octree::idx_set_x_mask;
|
|
// }
|
|
// else if (face_mask.y) {
|
|
// this_face_mask = Octree::idx_set_y_mask;
|
|
// }
|
|
// else if (face_mask.z) {
|
|
// this_face_mask = Octree::idx_set_z_mask;
|
|
// }
|
|
//
|
|
// traversal_state.idx_stack[traversal_state.scale] ^= this_face_mask;
|
|
//
|
|
// // Mask index is the 1D index'd value of the idx for interaction with the valid / leaf masks
|
|
// int mask_index = traversal_state.idx_stack[traversal_state.scale];
|
|
//
|
|
// // Whether or not the next oct we want to enter in the current CD's valid mask is 1 or 0
|
|
// bool is_valid = false;
|
|
//
|
|
// // TODO: Rework this logic so we don't have this bodgy if
|
|
// if (mask_index > prev_val)
|
|
// is_valid = (traversal_state.parent_stack[traversal_state.parent_stack_position] >> 16) & mask_8[mask_index];
|
|
//
|
|
// // Check to see if the idx increased or decreased
|
|
// // If it decreased
|
|
// // Pop up the stack until the oct that the idx flip is valid and we landed on a valid oct
|
|
// while (mask_index < prev_val || !is_valid) {
|
|
//
|
|
// jump_power *= 2;
|
|
//
|
|
// // Keep track of the 0th edge of out current oct
|
|
// traversal_state.oct_pos.x = floor(voxel.x / 2) * jump_power;
|
|
// traversal_state.oct_pos.y = floor(voxel.y / 2) * jump_power;
|
|
// traversal_state.oct_pos.z = floor(voxel.z / 2) * jump_power;
|
|
//
|
|
// // Clear and pop the idx stack
|
|
// traversal_state.idx_stack[traversal_state.scale] = 0;
|
|
//
|
|
// // Scale is now set to the oct above. Be wary of this
|
|
// traversal_state.scale--;
|
|
//
|
|
// // Update the prev_val for our new idx
|
|
// prev_val = traversal_state.idx_stack[traversal_state.scale];
|
|
//
|
|
// // Clear and pop the parent stack, maybe off by one error?
|
|
// traversal_state.parent_stack_index[traversal_state.parent_stack_position] = 0;
|
|
// traversal_state.parent_stack[traversal_state.parent_stack_position] = 0;
|
|
// traversal_state.parent_stack_position--;
|
|
//
|
|
// // Set the current CD to the one on top of the stack
|
|
// traversal_state.current_descriptor =
|
|
// traversal_state.parent_stack[traversal_state.parent_stack_position];
|
|
//
|
|
// // Apply the face mask to the new idx for the while check
|
|
// traversal_state.idx_stack[traversal_state.scale] ^= this_face_mask;
|
|
//
|
|
// // Get the mask index of the new idx and check the valid status
|
|
// mask_index = traversal_state.idx_stack[traversal_state.scale];
|
|
// is_valid = (traversal_state.parent_stack[traversal_state.parent_stack_position] >> 16) & mask_8[mask_index];
|
|
// }
|
|
//
|
|
// // At this point parent_stack[position] is at the CD of an oct with a valid oct at the leaf indicated by the current
|
|
// // idx in the idx stack scale
|
|
//
|
|
// // While we haven't bottomed out and the oct we're looking at is valid
|
|
// while (jump_power > 1 && is_valid) {
|
|
//
|
|
// // If all went well and we found a valid non-leaf oct then we will traverse further down the hierarchy
|
|
// traversal_state.scale++;
|
|
// jump_power /= 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 = count_bits((uint8_t)(traversal_state.parent_stack[traversal_state.parent_stack_position] >> 16) & count_mask_8[mask_index]) - 1;
|
|
//
|
|
// // If this CD had the far bit set
|
|
// if (far_bit_mask & descriptor_buffer[traversal_state.parent_stack_index[traversal_state.parent_stack_position]]) {
|
|
//
|
|
// // access the far point at which the head points too. Determine it's value, and add
|
|
// // the count of the valid bits in the current CD to the index
|
|
// uint64_t far_pointer_index =
|
|
// traversal_state.parent_stack_index[traversal_state.parent_stack_position] + // current index +
|
|
// (traversal_state.parent_stack[traversal_state.parent_stack_position] & child_pointer_mask); // the relative prt to the far ptr
|
|
//
|
|
// // Get the absolute ptr from the far ptr and add the count to get the CD that we want
|
|
// traversal_state.parent_stack_index[traversal_state.parent_stack_position + 1] = descriptor_buffer[far_pointer_index] + count;
|
|
// }
|
|
// // If this CD doesn't have the far bit set, access the element at which head points to
|
|
// // and then add the specified number of indices to get to the correct child descriptor
|
|
// else {
|
|
// traversal_state.parent_stack_index[traversal_state.parent_stack_position + 1] =
|
|
// traversal_state.parent_stack_index[traversal_state.parent_stack_position] + // The current index to this CD
|
|
// (traversal_state.parent_stack[traversal_state.parent_stack_position] & child_pointer_mask) + count; // The relative dist + the number of bits that were valid
|
|
// }
|
|
//
|
|
// // Now that we have the index set we can increase our parent stack position to the next level and
|
|
// // retrieve the value of its CD
|
|
// traversal_state.parent_stack_position++;
|
|
// traversal_state.parent_stack[traversal_state.parent_stack_position] = descriptor_buffer[traversal_state.parent_stack_index[traversal_state.parent_stack_position]];
|
|
//
|
|
// // Unlike the single shot DFS, it makes a bit more sense to have this at the tail of the while loop
|
|
// // Do the logic steps to find which sub oct we step down into
|
|
// if (voxel.x >= (jump_power / 2) + traversal_state.oct_pos.x) {
|
|
//
|
|
// // Set our voxel position to the (0,0) of the correct oct
|
|
// traversal_state.oct_pos.x += (jump_power / 2);
|
|
//
|
|
// // Set the idx to represent the move
|
|
// traversal_state.idx_stack[traversal_state.scale] |= idx_set_x_mask;
|
|
//
|
|
// }
|
|
// if (voxel.y >= (jump_power / 2) + traversal_state.oct_pos.y) {
|
|
//
|
|
// traversal_state.oct_pos.y += (jump_power / 2);
|
|
// traversal_state.idx_stack[traversal_state.scale] |= idx_set_y_mask;
|
|
// }
|
|
// if (voxel.z >= (jump_power / 2) + traversal_state.oct_pos.z) {
|
|
//
|
|
// traversal_state.oct_pos.z += (jump_power / 2);
|
|
// traversal_state.idx_stack[traversal_state.scale] |= idx_set_z_mask;
|
|
// }
|
|
//
|
|
// // Update the mask index with the new voxel we walked down to, and then check it's valid status
|
|
// mask_index = traversal_state.idx_stack[traversal_state.scale];
|
|
// is_valid = (traversal_state.parent_stack[traversal_state.parent_stack_position] >> 16) & mask_8[mask_index];
|
|
//
|
|
// }
|
|
|
|
// =======================================================================================================================================
|
|
// =======================================================================================================================================
|
|
// =======================================================================================================================================
|
|
|
|
// 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;
|
|
}
|
|
|
|
int vox_dim = OCTDIM;
|
|
|
|
// If we hit a voxel
|
|
// if (voxel.x < (*map_dim).x && voxel.y < (*map_dim).x && voxel.z < (*map_dim).x){
|
|
// 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 == 5 || voxel_data == 6) {
|
|
// 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)(1.00001f, 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, 1.00001f, 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, 1.00001f);
|
|
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 RAY 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)(5, 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 + fast_distance(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;
|
|
|
|
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);
|
|
|
|
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.w = 0.1f;
|
|
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;
|
|
}
|