Task 068: .BSK File Format
Task 068: .BSK File Format
1. Properties of the .BSK File Format
The .BSK file format is primarily associated with Bryce, a 3D landscape modeling application developed by DAZ Productions. It is used to store visual properties for rendering skies in 3D scenes, including settings for daytime, nighttime, or outer space environments, as well as elements such as clouds and fog. The properties intrinsic to the file structure are the parameters that define these visual elements. Based on available descriptions, these include:
- Sun position (coordinates in 3D space).
- Sun color and intensity.
- Cloud density and height.
- Cloud type and texture.
- Fog density and color.
- Atmosphere color gradient.
- Star density and brightness.
- Overall sky brightness and hue.
These properties are stored in a binary format, but detailed byte-level specifications are not publicly available. The above list is derived from functional descriptions of the file's content.
2. Direct Download Links for .BSK Files
After extensive search, direct download links for .BSK files are limited, as most are hosted on sites requiring registration or are bundled in ZIP archives. Two sources providing free .BSK files are:
- https://www.renderosity.com/files/upload/80972/40_sky_presets_for_Bryce_7.zip (a ZIP archive containing 40 sky presets in .BSK format).
- https://www.horo.ch/docs/mine/zip/Bryce7ProSkyToolbox.zip (a ZIP archive with sky toolbox presets including .BSK files).
Note: These links may require account creation for access, as they are from community sharing platforms.
3. Ghost Blog Embedded HTML JavaScript for Drag-and-Drop .BSK File Dump
The following is an embedded HTML page with JavaScript that can be used in a Ghost blog post. It allows users to drag and drop a .BSK file, parses it based on a hypothetical binary structure (since no public specification is available), and displays the properties on the screen. The assumed structure is:
- Bytes 0-3: Magic signature ('BSK ').
- Bytes 4-7: Version (int32).
- Bytes 8-19: Sun position (3 float32).
- Bytes 20-31: Sun color (3 float32).
- Bytes 32-35: Cloud density (float32).
- Bytes 36-39: Fog density (float32).
Note: This implementation uses a hypothetical structure, as the actual binary format is proprietary and not documented publicly. In practice, reverse engineering would be required for accurate parsing.
4. Python Class for .BSK File Handling
The following Python class opens, decodes, reads, writes, and prints .BSK file properties based on the hypothetical structure described above. It uses the struct module for binary parsing.
import struct
class BSKHandler:
def __init__(self, filepath):
self.filepath = filepath
self.magic = b'BSK '
self.version = 1
self.sun_position = (0.0, 0.0, 0.0)
self.sun_color = (1.0, 1.0, 1.0)
self.cloud_density = 0.5
self.fog_density = 0.2
def read(self):
with open(self.filepath, 'rb') as f:
data = f.read()
if len(data) < 40:
raise ValueError("File too small for .BSK format.")
self.magic = data[0:4]
if self.magic != b'BSK ':
raise ValueError("Invalid magic signature.")
self.version = struct.unpack('<i', data[4:8])[0]
self.sun_position = struct.unpack('<fff', data[8:20])
self.sun_color = struct.unpack('<fff', data[20:32])
self.cloud_density = struct.unpack('<f', data[32:36])[0]
self.fog_density = struct.unpack('<f', data[36:40])[0]
def print_properties(self):
print(f"Magic: {self.magic.decode()}")
print(f"Version: {self.version}")
print(f"Sun Position: {self.sun_position}")
print(f"Sun Color: {self.sun_color}")
print(f"Cloud Density: {self.cloud_density}")
print(f"Fog Density: {self.fog_density}")
def write(self):
with open(self.filepath, 'wb') as f:
f.write(self.magic)
f.write(struct.pack('<i', self.version))
f.write(struct.pack('<fff', *self.sun_position))
f.write(struct.pack('<fff', *self.sun_color))
f.write(struct.pack('<f', self.cloud_density))
f.write(struct.pack('<f', self.fog_density))
# Example usage:
# handler = BSKHandler('example.bsk')
# handler.read()
# handler.print_properties()
# handler.sun_position = (1.0, 2.0, 3.0)
# handler.write()
Note: This class assumes a hypothetical structure, as the actual format is proprietary. To arrive at the solution for closed-ended mathematics questions, n/a in this case, as no math is involved.
5. Java Class for .BSK File Handling
The following Java class opens, decodes, reads, writes, and prints .BSK file properties using ByteBuffer for binary parsing.
import java.io.RandomAccessFile;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.channels.FileChannel;
public class BSKHandler {
private String filepath;
private String magic = "BSK ";
private int version = 1;
private float[] sunPosition = {0.0f, 0.0f, 0.0f};
private float[] sunColor = {1.0f, 1.0f, 1.0f};
private float cloudDensity = 0.5f;
private float fogDensity = 0.2f;
public BSKHandler(String filepath) {
this.filepath = filepath;
}
public void read() throws Exception {
try (RandomAccessFile file = new RandomAccessFile(filepath, "r")) {
FileChannel channel = file.getChannel();
ByteBuffer buffer = ByteBuffer.allocate(40).order(ByteOrder.LITTLE_ENDIAN);
channel.read(buffer);
buffer.flip();
byte[] magicBytes = new byte[4];
buffer.get(magicBytes);
magic = new String(magicBytes);
if (!magic.equals("BSK ")) {
throw new Exception("Invalid magic signature.");
}
version = buffer.getInt();
sunPosition[0] = buffer.getFloat();
sunPosition[1] = buffer.getFloat();
sunPosition[2] = buffer.getFloat();
sunColor[0] = buffer.getFloat();
sunColor[1] = buffer.getFloat();
sunColor[2] = buffer.getFloat();
cloudDensity = buffer.getFloat();
fogDensity = buffer.getFloat();
}
}
public void printProperties() {
System.out.println("Magic: " + magic);
System.out.println("Version: " + version);
System.out.println("Sun Position: (" + sunPosition[0] + ", " + sunPosition[1] + ", " + sunPosition[2] + ")");
System.out.println("Sun Color: (" + sunColor[0] + ", " + sunColor[1] + ", " + sunColor[2] + ")");
System.out.println("Cloud Density: " + cloudDensity);
System.out.println("Fog Density: " + fogDensity);
}
public void write() throws Exception {
try (RandomAccessFile file = new RandomAccessFile(filepath, "rw")) {
FileChannel channel = file.getChannel();
ByteBuffer buffer = ByteBuffer.allocate(40).order(ByteOrder.LITTLE_ENDIAN);
buffer.put(magic.getBytes());
buffer.putInt(version);
buffer.putFloat(sunPosition[0]);
buffer.putFloat(sunPosition[1]);
buffer.putFloat(sunPosition[2]);
buffer.putFloat(sunColor[0]);
buffer.putFloat(sunColor[1]);
buffer.putFloat(sunColor[2]);
buffer.putFloat(cloudDensity);
buffer.putFloat(fogDensity);
buffer.flip();
channel.write(buffer);
}
}
// Example usage:
// BSKHandler handler = new BSKHandler("example.bsk");
// handler.read();
// handler.printProperties();
// handler.sunPosition = new float[]{1.0f, 2.0f, 3.0f};
// handler.write();
}
Note: This class assumes a hypothetical structure, as the actual format is proprietary.
6. JavaScript Class for .BSK File Handling
The following JavaScript class opens, decodes, reads, writes, and prints .BSK file properties using FileReader and DataView. It is designed for browser use.
class BSKHandler {
constructor(filepath) {
this.filepath = filepath;
this.magic = 'BSK ';
this.version = 1;
this.sunPosition = [0.0, 0.0, 0.0];
this.sunColor = [1.0, 1.0, 1.0];
this.cloudDensity = 0.5;
this.fogDensity = 0.2;
}
async read(file) {
return new Promise((resolve, reject) => {
const reader = new FileReader();
reader.onload = (event) => {
const arrayBuffer = event.target.result;
const view = new DataView(arrayBuffer);
const magic = String.fromCharCode(view.getUint8(0), view.getUint8(1), view.getUint8(2), view.getUint8(3));
if (magic !== 'BSK ') {
reject('Invalid magic signature.');
}
this.version = view.getInt32(4, true);
this.sunPosition = [view.getFloat32(8, true), view.getFloat32(12, true), view.getFloat32(16, true)];
this.sunColor = [view.getFloat32(20, true), view.getFloat32(24, true), view.getFloat32(28, true)];
this.cloudDensity = view.getFloat32(32, true);
this.fogDensity = view.getFloat32(36, true);
resolve();
};
reader.readAsArrayBuffer(file);
});
}
printProperties() {
console.log(`Magic: ${this.magic}`);
console.log(`Version: ${this.version}`);
console.log(`Sun Position: (${this.sunPosition.join(', ')})`);
console.log(`Sun Color: (${this.sunColor.join(', ')})`);
console.log(`Cloud Density: ${this.cloudDensity}`);
console.log(`Fog Density: ${this.fogDensity}`);
}
write() {
// Writing in browser is limited; this generates a Blob for download.
const buffer = new ArrayBuffer(40);
const view = new DataView(buffer);
for (let i = 0; i < 4; i++) {
view.setUint8(i, this.magic.charCodeAt(i));
}
view.setInt32(4, this.version, true);
view.setFloat32(8, this.sunPosition[0], true);
view.setFloat32(12, this.sunPosition[1], true);
view.setFloat32(16, this.sunPosition[2], true);
view.setFloat32(20, this.sunColor[0], true);
view.setFloat32(24, this.sunColor[1], true);
view.setFloat32(28, this.sunColor[2], true);
view.setFloat32(32, this.cloudDensity, true);
view.setFloat32(36, this.fogDensity, true);
const blob = new Blob([buffer], { type: 'application/octet-stream' });
const url = URL.createObjectURL(blob);
const a = document.createElement('a');
a.href = url;
a.download = 'modified.bsk';
a.click();
URL.revokeObjectURL(url);
}
}
// Example usage:
// const handler = new BSKHandler('example.bsk');
// Assume 'file' is a File object from input
// await handler.read(file);
// handler.printProperties();
// handler.sunPosition = [1.0, 2.0, 3.0];
// handler.write();
Note: This class assumes a hypothetical structure, as the actual format is proprietary. Writing generates a downloadable file.
7. C Class for .BSK File Handling
The following C code defines a struct and functions to open, decode, read, write, and print .BSK file properties using binary I/O. It assumes the hypothetical structure.
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
typedef struct {
char magic[5];
int version;
float sunPosition[3];
float sunColor[3];
float cloudDensity;
float fogDensity;
} BSKData;
void readBSK(const char* filepath, BSKData* data) {
FILE* file = fopen(filepath, "rb");
if (!file) {
printf("Unable to open file.\n");
exit(1);
}
fread(data->magic, 1, 4, file);
data->magic[4] = '\0';
if (strcmp(data->magic, "BSK ") != 0) {
printf("Invalid magic signature.\n");
fclose(file);
exit(1);
}
fread(&data->version, sizeof(int), 1, file);
fread(data->sunPosition, sizeof(float), 3, file);
fread(data->sunColor, sizeof(float), 3, file);
fread(&data->cloudDensity, sizeof(float), 1, file);
fread(&data->fogDensity, sizeof(float), 1, file);
fclose(file);
}
void printBSKProperties(const BSKData* data) {
printf("Magic: %s\n", data->magic);
printf("Version: %d\n", data->version);
printf("Sun Position: (%.2f, %.2f, %.2f)\n", data->sunPosition[0], data->sunPosition[1], data->sunPosition[2]);
printf("Sun Color: (%.2f, %.2f, %.2f)\n", data->sunColor[0], data->sunColor[1], data->sunColor[2]);
printf("Cloud Density: %.2f\n", data->cloudDensity);
printf("Fog Density: %.2f\n", data->fogDensity);
}
void writeBSK(const char* filepath, const BSKData* data) {
FILE* file = fopen(filepath, "wb");
if (!file) {
printf("Unable to open file for writing.\n");
exit(1);
}
fwrite(data->magic, 1, 4, file);
fwrite(&data->version, sizeof(int), 1, file);
fwrite(data->sunPosition, sizeof(float), 3, file);
fwrite(data->sunColor, sizeof(float), 3, file);
fwrite(&data->cloudDensity, sizeof(float), 1, file);
fwrite(&data->fogDensity, sizeof(float), 1, file);
fclose(file);
}
// Example usage:
// int main() {
// BSKData data;
// readBSK("example.bsk", &data);
// printBSKProperties(&data);
// data.sunPosition[0] = 1.0;
// writeBSK("modified.bsk", &data);
// return 0;
// }
Note: This C implementation assumes a hypothetical structure, as the actual format is proprietary. Byte order is assumed little-endian.