initial commit, 4.5 stable

servers/rendering/renderer_rd/shaders/environment/voxel_gi_sdf.glsl

@@ -0,0 +1,180 @@
+#[compute]
+
+#version 450
+
+#VERSION_DEFINES
+
+layout(local_size_x = 4, local_size_y = 4, local_size_z = 4) in;
+
+#define MAX_DISTANCE 100000.0
+
+#define NO_CHILDREN 0xFFFFFFFF
+
+struct CellChildren {
+	uint children[8];
+};
+
+layout(set = 0, binding = 1, std430) buffer CellChildrenBuffer {
+	CellChildren data[];
+}
+cell_children;
+
+struct CellData {
+	uint position; // xyz 10 bits
+	uint albedo; //rgb albedo
+	uint emission; //rgb normalized with e as multiplier
+	uint normal; //RGB normal encoded
+};
+
+layout(set = 0, binding = 2, std430) buffer CellDataBuffer {
+	CellData data[];
+}
+cell_data;
+
+layout(r8ui, set = 0, binding = 3) uniform restrict writeonly uimage3D sdf_tex;
+
+layout(push_constant, std430) uniform Params {
+	uint offset;
+	uint end;
+	uint pad0;
+	uint pad1;
+}
+params;
+
+void main() {
+	vec3 pos = vec3(gl_GlobalInvocationID);
+	float closest_dist = MAX_DISTANCE;
+
+	for (uint i = params.offset; i < params.end; i++) {
+		vec3 posu = vec3(uvec3(cell_data.data[i].position & 0x7FF, (cell_data.data[i].position >> 11) & 0x3FF, cell_data.data[i].position >> 21));
+		float dist = length(pos - posu);
+		if (dist < closest_dist) {
+			closest_dist = dist;
+		}
+	}
+
+	uint dist_8;
+
+	if (closest_dist < 0.0001) { // same cell
+		dist_8 = 0; //equals to -1
+	} else {
+		dist_8 = clamp(uint(closest_dist), 0, 254) + 1; //conservative, 0 is 1, so <1 is considered solid
+	}
+
+	imageStore(sdf_tex, ivec3(gl_GlobalInvocationID), uvec4(dist_8));
+	//imageStore(sdf_tex,pos,uvec4(pos*2,0));
+}
+
+#if 0
+layout(push_constant, std430) uniform Params {
+	ivec3 limits;
+	uint stack_size;
+}
+params;
+
+float distance_to_aabb(ivec3 pos, ivec3 aabb_pos, ivec3 aabb_size) {
+	vec3 delta = vec3(max(ivec3(0), max(aabb_pos - pos, pos - (aabb_pos + aabb_size - ivec3(1)))));
+	return length(delta);
+}
+
+void main() {
+	ivec3 pos = ivec3(gl_GlobalInvocationID);
+
+	uint stack[10] = uint[](0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
+	uint stack_indices[10] = uint[](0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
+	ivec3 stack_positions[10] = ivec3[](ivec3(0), ivec3(0), ivec3(0), ivec3(0), ivec3(0), ivec3(0), ivec3(0), ivec3(0), ivec3(0), ivec3(0));
+
+	const uint cell_orders[8] = uint[](
+			0x11f58d1,
+			0xe2e70a,
+			0xd47463,
+			0xbb829c,
+			0x8d11f5,
+			0x70ae2e,
+			0x463d47,
+			0x29cbb8);
+
+	bool cell_found = false;
+	bool cell_found_exact = false;
+	ivec3 closest_cell_pos;
+	float closest_distance = MAX_DISTANCE;
+	int stack_pos = 0;
+
+	while (true) {
+		uint index = stack_indices[stack_pos] >> 24;
+
+		if (index == 8) {
+			//go up
+			if (stack_pos == 0) {
+				break; //done going through octree
+			}
+			stack_pos--;
+			continue;
+		}
+
+		stack_indices[stack_pos] = (stack_indices[stack_pos] & ((1 << 24) - 1)) | ((index + 1) << 24);
+
+		uint cell_index = (stack_indices[stack_pos] >> (index * 3)) & 0x7;
+		uint child_cell = cell_children.data[stack[stack_pos]].children[cell_index];
+
+		if (child_cell == NO_CHILDREN) {
+			continue;
+		}
+
+		ivec3 child_cell_size = params.limits >> (stack_pos + 1);
+		ivec3 child_cell_pos = stack_positions[stack_pos];
+
+		child_cell_pos += mix(ivec3(0), child_cell_size, bvec3(uvec3(index & 1, index & 2, index & 4) != uvec3(0)));
+
+		bool is_leaf = stack_pos == (params.stack_size - 2);
+
+		if (child_cell_pos == pos && is_leaf) {
+			//we may actually end up in the exact cell.
+			//if this happens, just abort
+			cell_found_exact = true;
+			break;
+		}
+
+		if (cell_found) {
+			//discard by distance
+			float distance = distance_to_aabb(pos, child_cell_pos, child_cell_size);
+			if (distance >= closest_distance) {
+				continue; //pointless, just test next child
+			} else if (is_leaf) {
+				//closer than what we have AND end of stack, save and continue
+				closest_cell_pos = child_cell_pos;
+				closest_distance = distance;
+				continue;
+			}
+		} else if (is_leaf) {
+			//first solid cell we find, save and continue
+			closest_distance = distance_to_aabb(pos, child_cell_pos, child_cell_size);
+			closest_cell_pos = child_cell_pos;
+			cell_found = true;
+			continue;
+		}
+
+		bvec3 direction = greaterThan((pos - (child_cell_pos + (child_cell_size >> 1))), ivec3(0));
+		uint cell_order = 0;
+		cell_order |= mix(0, 1, direction.x);
+		cell_order |= mix(0, 2, direction.y);
+		cell_order |= mix(0, 4, direction.z);
+
+		stack[stack_pos + 1] = child_cell;
+		stack_indices[stack_pos + 1] = cell_orders[cell_order]; //start counting
+		stack_positions[stack_pos + 1] = child_cell_pos;
+		stack_pos++; //go up stack
+	}
+
+	uint dist_8;
+
+	if (cell_found_exact) {
+		dist_8 = 0; //equals to -1
+	} else {
+		float closest_distance = length(vec3(pos - closest_cell_pos));
+		dist_8 = clamp(uint(closest_distance), 0, 254) + 1; //conservative, 0 is 1, so <1 is considered solid
+	}
+
+	imageStore(sdf_tex, pos, uvec4(dist_8));
+}
+#endif