porky11 · August 13, 2019 15:33
diff --git a/voxel.comp b/voxel.comp
 #version 460
 layout(local_size_x = 4, local_size_y = 4, local_size_z = 4) in;

 struct Sphere {
    vec4 center;
 };

 layout(binding = 1, std140) uniform Camera {
    vec4 pos;
    vec4 dir;
 } camera;

 layout(binding = 1, std430) buffer Shapes {
    Sphere shapes[16];
 } shapes;

 layout(binding = 0, std430) buffer ShapeCount {
    uint count;
 } shape_count;

 layout(binding = 0, r32f) uniform writeonly image3D voxel_image;

 vec4 multiply_quat(vec4 quat, vec3 vec) {
    return vec4(
        quat.x * vec.x + quat.y * vec.y + quat.z * vec.z,
        quat.x * vec.y - quat.y * vec.x + quat.w * vec.z,
        quat.x * vec.z - quat.z * vec.x - quat.w * vec.y,
        quat.y * vec.z - quat.z * vec.y + quat.w * vec.x
    );
 }

 vec3 rotate_back(vec4 rotated, vec4 quat) {
    return vec3(
        rotated.x * quat.x - rotated.y * quat.y - rotated.z * quat.z - rotated.w * quat.w,
        rotated.x * quat.y + rotated.y * quat.x - rotated.z * quat.w + rotated.w * quat.z,
        rotated.x * quat.z + rotated.y * quat.w + rotated.z * quat.x - rotated.w * quat.y
    );
 }

 float len2(vec3 disvec) {
    return (disvec.x * disvec.x + disvec.y * disvec.y + disvec.z * disvec.z);
 }

 float field_distance(vec3 p) {
    Sphere shapes[16] = shapes.shapes;
    float minimum_distance = 4096.0;
    for (uint i = 0u; i < shape_count.count; ++i) {
        vec3 disvec = (p - shapes[i].center.xyz);
        float new_distance = sqrt(abs(len2(disvec))) - 1.0;
        minimum_distance = (new_distance < minimum_distance) ? new_distance : minimum_distance;
    }
    return minimum_distance;
 }

 void main() {
    uvec3 index = (gl_GlobalInvocationID * gl_WorkGroupSize) + gl_LocalInvocationID;
    vec3 p = vec3(index.x - 32u, index.y - 32u, -64.0);
    float len = sqrt(abs(len2(p)));
    vec4 conjugate_quat = vec4(1, -1, -1, -1);
    float d = 1.0 + (float(index.z) / float(16u));
    imageStore(voxel_image, ivec3(index), vec4(field_distance((camera.pos.xyz + rotate_back(multiply_quat(camera.dir, p / len), camera.dir * conjugate_quat) * d)), 0, 0, 0));
 }
	#version 460
	layout(local_size_x = 4, local_size_y = 4, local_size_z = 4) in;

	struct Sphere {
	vec4 center;
	};

	layout(binding = 1, std140) uniform Camera {
	vec4 pos;
	vec4 dir;
	} camera;

	layout(binding = 1, std430) buffer Shapes {
	Sphere shapes[16];
	} shapes;

	layout(binding = 0, std430) buffer ShapeCount {
	uint count;
	} shape_count;

	layout(binding = 0, r32f) uniform writeonly image3D voxel_image;

	vec4 multiply_quat(vec4 quat, vec3 vec) {
	return vec4(
	quat.x * vec.x + quat.y * vec.y + quat.z * vec.z,
	quat.x * vec.y - quat.y * vec.x + quat.w * vec.z,
	quat.x * vec.z - quat.z * vec.x - quat.w * vec.y,
	quat.y * vec.z - quat.z * vec.y + quat.w * vec.x
	);
	}

	vec3 rotate_back(vec4 rotated, vec4 quat) {
	return vec3(
	rotated.x * quat.x - rotated.y * quat.y - rotated.z * quat.z - rotated.w * quat.w,
	rotated.x * quat.y + rotated.y * quat.x - rotated.z * quat.w + rotated.w * quat.z,
	rotated.x * quat.z + rotated.y * quat.w + rotated.z * quat.x - rotated.w * quat.y
	);
	}

	float len2(vec3 disvec) {
	return (disvec.x * disvec.x + disvec.y * disvec.y + disvec.z * disvec.z);
	}

	float field_distance(vec3 p) {
	Sphere shapes[16] = shapes.shapes;
	float minimum_distance = 4096.0;
	for (uint i = 0u; i < shape_count.count; ++i) {
	vec3 disvec = (p - shapes[i].center.xyz);
	float new_distance = sqrt(abs(len2(disvec))) - 1.0;
	minimum_distance = (new_distance < minimum_distance) ? new_distance : minimum_distance;
	}
	return minimum_distance;
	}

	void main() {
	uvec3 index = (gl_GlobalInvocationID * gl_WorkGroupSize) + gl_LocalInvocationID;
	vec3 p = vec3(index.x - 32u, index.y - 32u, -64.0);
	float len = sqrt(abs(len2(p)));
	vec4 conjugate_quat = vec4(1, -1, -1, -1);
	float d = 1.0 + (float(index.z) / float(16u));
	imageStore(voxel_image, ivec3(index), vec4(field_distance((camera.pos.xyz + rotate_back(multiply_quat(camera.dir, p / len), camera.dir * conjugate_quat) * d)), 0, 0, 0));
	}