Write Grid Resolution Frames

2023-11-28 17:45 UTC gpt-4 Open in ChatGPT ↗

You

import c4d

def write_frame_data(filePath, frame_data): with open(filePath, “a”) as file: file.write(frame_data + “\n”)

def main(): matrix_object = op.GetObject() if not matrix_object: print(“Object not found”) return

grid_resolution = matrix_object[c4d.MG_GRID_RESOLUTION]
if grid_resolution is None:
    print("Grid resolution data not found")
    return

x_count = int(grid_resolution.x)
z_count = int(grid_resolution.z)

startFrame = doc.GetLoopMinTime().GetFrame(doc.GetFps())
endFrame = doc.GetLoopMaxTime().GetFrame(doc.GetFps())
totalFrames = endFrame - startFrame + 1

md = c4d.modules.mograph.GeGetMoData(matrix_object)
if md is None:
    print("MoGraph data not found")
    return

colors = md.GetArray(c4d.MODATA_COLOR)
matrices = md.GetArray(c4d.MODATA_MATRIX)  # Get matrix data
if colors is None or matrices is None:
    print("Color or matrix data not found")
    return

#frame_data = ",".join(f"{int(color.x*255)}, {int(color.y*255)}, {int(color.z*255)}, {round(matrix.GetScale().x, 2)}" for color, matrix in zip(colors, matrices))
frame_data = ",".join(f"{int(color.x*255)}, {round(matrix.GetScale().x, 2)}" for color, matrix in zip(colors, matrices))

currentFrame = doc.GetTime().GetFrame(doc.GetFps())

filePath = f"H:/My Drive/02_Projects/41_SPTF_FCBNY Spotify/00_Research and Development/C4D/Sketching/231122 Write Values from C4D/Written/matrix_color_&_scale_timeline_{x_count}x{z_count}_{totalFrames}_frames.txt"

write_frame_data(filePath, frame_data)
print(f"Color and scale data for frame {currentFrame} written to file")

if name==‘main’: main()

This works for writing the colour and scale values of a Cinema 4D matrix to a text file each frame. Instead I now want to only write the grid resolution each frame

ChatGPT

To modify your script so that it writes the grid resolution of a Cinema 4D matrix object to a text file for each frame, you need to change a few parts of the script. Here’s an updated version of your script with the necessary changes:

import c4d

def write_frame_data(filePath, frame_data):
    with open(filePath, "a") as file:
        file.write(frame_data + "\n")

def main():
    matrix_object = op.GetObject()
    if not matrix_object:
        print("Object not found")
        return

    grid_resolution = matrix_object[c4d.MG_GRID_RESOLUTION]
    if grid_resolution is None:
        print("Grid resolution data not found")
        return

    x_count = int(grid_resolution.x)
    z_count = int(grid_resolution.z)

    startFrame = doc.GetLoopMinTime().GetFrame(doc.GetFps())
    endFrame = doc.GetLoopMaxTime().GetFrame(doc.GetFps())
    totalFrames = endFrame - startFrame + 1

    currentFrame = doc.GetTime().GetFrame(doc.GetFps())

    frame_data = f"Frame: {currentFrame}, Grid Resolution: {x_count}x{z_count}"

    filePath = f"H:/My Drive/02_Projects/41_SPTF_FCBNY Spotify/00_Research and Development/C4D/Sketching/231122 Write Values from C4D/Written/grid_resolution_timeline_{x_count}x{z_count}_{totalFrames}_frames.txt"

    write_frame_data(filePath, frame_data)
    print(f"Grid resolution data for frame {currentFrame} written to file")

if __name__=='__main__':
    main()

In this updated script:

1. I removed the code that fetches and processes the color and matrix data, as it’s no longer needed for just writing the grid resolution.
2. The frame_data string is updated to include only the current frame number and the grid resolution (x and z counts).
3. The file path and the message printed to the console are updated to reflect that it’s the grid resolution being written, not the color and scale data.

You

This creates a new file everytime the grid resolution changes. Can we instead append this all to one file

ChatGPT

Certainly! To append the grid resolution data for each frame to a single file, you need to ensure that the file path is constant and not dependent on the grid resolution. This way, data from all frames will be written to the same file. Here’s the revised script:

import c4d

def write_frame_data(filePath, frame_data):
    with open(filePath, "a") as file:
        file.write(frame_data + "\n")

def main():
    matrix_object = op.GetObject()
    if not matrix_object:
        print("Object not found")
        return

    grid_resolution = matrix_object[c4d.MG_GRID_RESOLUTION]
    if grid_resolution is None:
        print("Grid resolution data not found")
        return

    x_count = int(grid_resolution.x)
    z_count = int(grid_resolution.z)

    currentFrame = doc.GetTime().GetFrame(doc.GetFps())

    frame_data = f"Frame: {currentFrame}, Grid Resolution: {x_count}x{z_count}"

    filePath = "H:/My Drive/02_Projects/41_SPTF_FCBNY Spotify/00_Research and Development/C4D/Sketching/231122 Write Values from C4D/Written/grid_resolution_data.txt"

    write_frame_data(filePath, frame_data)
    print(f"Grid resolution data for frame {currentFrame} written to file")

if __name__=='__main__':
    main()

Changes made:

1. The filePath is now set to a constant value, meaning it does not change with the grid resolution. This ensures that all data will be appended to the same file.
2. The parts of the script that calculate the total number of frames and the start/end frames are removed as they are not needed for appending data to a single file.

With this modification, every time the script runs for a frame, it will append the grid resolution data of that frame to the specified file, creating a continuous log of the grid resolution over time.

You

In cinema 4d xpresso, how do I access an objects scale value that is affected by effectors, not it’s basic scale

ChatGPT

Accessing the scale value of an object in Cinema 4D that is being affected by MoGraph effectors, especially within Xpresso, can be a bit tricky. This is because the effectors often modify the scale at a level that isn’t directly reflected in the object’s basic parameters.

To access the scale value of an object as it is after being affected by MoGraph effectors, you need to use the MoGraph Data node in Xpresso. This node allows you to extract various types of data from MoGraph objects, including the scale as affected by effectors. Here’s a basic outline of how you can do this:

1. Create a MoGraph Data Node:

   • Open the Xpresso editor and create a MoGraph Data node. You can find this under the MoGraph menu in the Xpresso node browser.

2. Set the MoGraph Object:

   • Drag your MoGraph object (like a Cloner or Matrix object) into the Xpresso editor. This will create a node for the object.
   • Connect the object node to the MoGraph Data node. For example, if it’s a Cloner object, you’d connect the Cloner node to the MoGraph Data node.

3. Configure the MoGraph Data Node:

   • In the MoGraph Data node, you need to set it to retrieve the right kind of data. In the attributes of the node, set it to retrieve the ‘Matrix’ or ‘Scale’ data.
   • If you choose ‘Matrix’, you will get the transformation matrix of each clone, which includes scale information. If you choose ‘Scale’, you will get just the scale vector.

4. Extract the Scale Information:

   • You will likely need to use additional nodes to extract the specific scale values from the data provided by the MoGraph Data node. For example, if you’re using the Matrix data, you might need a Matrix2Vectors node to break down the matrix into position, scale, and rotation vectors.

5. Use the Data as Needed:

   • Now that you have the scale data, you can connect it to other nodes within your Xpresso setup to drive other parameters or calculations.

Remember that MoGraph Data node will provide information about all clones or elements in your MoGraph setup. If you need data for a specific clone, you’ll have to specify its index (i.e., which clone number you want the data for).

Also, note that this approach gives you the final transformation matrix of each element, which includes the combined effects of all transformations (position, rotation, scale) and is influenced by all effectors affecting the object. If you only need the scale component, be sure to isolate it properly.

You

This works, how do I ensure the scale value returned to the grid count is an integer instead of a float

ChatGPT

To ensure that the scale value you retrieve from a MoGraph object in Cinema 4D using Xpresso is an integer instead of a float, you can use the Math node within the Xpresso setup. The Math node can perform a variety of mathematical operations, including rounding, which can convert the float scale values to integers.

Here’s how you can incorporate this into your Xpresso setup:

1. Add a Math Node:

   • Create a Math node in your Xpresso editor. You can find this under the ‘New Node’ -> ‘Xpresso’ -> ‘Calculate’ -> ‘Math’.

2. Configure the Math Node:

   • Set the Math node’s operation to either ‘Round’, ‘Floor’, or ‘Ceil’, depending on how you want to handle the conversion to integer:
     • ‘Round’ will round the number to the nearest integer.
     • ‘Floor’ will round the number down to the nearest integer.
     • ‘Ceil’ will round the number up to the nearest integer.

3. Connect the Scale Output to the Math Node:

   • Connect the scale output from the MoGraph Data node (or whichever node is outputting the scale values) to the input of the Math node.

4. Output the Rounded Value:

   • The output of the Math node can now be used as an integer value in your Xpresso setup. Connect this output to wherever you need the integer scale value.

This setup ensures that the scale values, which are initially floats, are converted to integers before being used further in your Xpresso setup. This is particularly useful if you need to use these values in contexts where integer values are required or more appropriate.

You

The math node function only contains: add, subtract, multiply, divide and modulo

ChatGPT

In Cinema 4D’s Xpresso, if the Math node does not provide rounding functions like ‘Round’, ‘Floor’, or ‘Ceil’, you can achieve integer conversion using a combination of other nodes. One common approach is to use the combination of a Math node and a Logic node.

Here’s a step-by-step guide:

1. Use a Math Node to Multiply and Divide:

   • First, add a Math node to your Xpresso setup.
   • Set the operation to ‘Multiply’.
   • Connect the scale output (float value) to the first input of the Math node.
   • Set the second input of the Math node to a large number, like 1000 or 10000. This temporarily converts the float to a large integer by shifting the decimal point.

2. Add Another Math Node for Modulo Operation:

   • Add another Math node.
   • Set this one’s operation to ‘Modulo’.
   • Connect the output of the first Math node to the first input of the Modulo node.
   • Set the second input of the Modulo node to the same value you used for multiplication (e.g., 1000 or 10000).

3. Use a Math Node to Divide:

   • Add one more Math node.
   • Set this one’s operation to ‘Divide’.
   • Connect the output of the Modulo node to the first input of the Divide node.
   • Set the second input of the Divide node to the same value you used before (e.g., 1000 or 10000). This scales the value back down, effectively rounding it off.

4. Finalize and Connect Your Nodes:

   • The output of the last Divide node should now be a rounded integer value.
   • Connect this output to wherever you need the integer scale value in your Xpresso setup.

This method essentially magnifies the float value to a large number where the decimal points become insignificant, uses modulo to trim off any excess, and then scales it back down, resulting in an integer value. The choice of the multiplier/divider (like 1000 or 10000) depends on how many decimal places you expect in your original float value. The higher the number, the more precise the operation, but it also increases the risk of hitting a limit for large values.

You

This hasnt worked

ChatGPT

If the previous method didn’t work, let’s try a different approach using Python in an Xpresso setup. Cinema 4D’s Python node in Xpresso allows you to write custom scripts, which can be used for tasks like rounding a float to an integer.

Here’s how you can set up a Python node to round a float value to an integer:

1. Create a Python Node:

   • In your Xpresso editor, create a Python node. This can typically be found under ‘New Node’ -> ‘Xpresso’ -> ‘Script’ -> ‘Python’.

2. Configure the Python Node:

   • Define input and output ports in the Python node. You’ll need a float input port for the scale value and an integer output port for the rounded result.

3. Write the Python Script:

   • Double-click on the Python node to open the script editor. Write a script to round the input value and output it. Here’s a simple example:

     import c4d
     
     def main():
         global Output1  # Output1 is your integer output port
         Output1 = int(round(Input1))  # Input1 is your float input port

   • This script takes the float value from Input1, rounds it using Python’s built-in round function, converts it to an integer, and assigns it to the output port Output1.

4. Connect Your Nodes:

   • Connect the scale output (float value) from the MoGraph Data node (or whichever node is outputting the scale values) to the input of the Python node.
   • Connect the output of the Python node to wherever you need the integer scale value in your Xpresso setup.

This method should reliably round your float values to the nearest integer using Python, which can handle this operation without the limitations of the standard Math node.

You

perfect, thank you

ChatGPT

You’re welcome! I’m glad to hear that the solution worked for you. If you have any more questions, whether they’re about Cinema 4D, Xpresso, Python scripting, or anything else, feel free to ask. Happy creating!

You

This code works perfectly:

import c4d

def write_frame_data(filePath, frame_data): with open(filePath, “a”) as file: file.write(frame_data + “\n”)

def main(): matrix_object = op.GetObject() if not matrix_object: print(“Object not found”) return

grid_resolution = matrix_object[c4d.MG_GRID_RESOLUTION]
if grid_resolution is None:
    print("Grid resolution data not found")
    return

x_count = int(grid_resolution.x)
z_count = int(grid_resolution.z)

currentFrame = doc.GetTime().GetFrame(doc.GetFps())

frame_data = f"Frame: {currentFrame}, Grid Resolution: {x_count}x{z_count}"

filePath = "H:/My Drive/02_Projects/41_SPTF_FCBNY Spotify/00_Research and Development/C4D/Sketching/231122 Write Values from C4D/Written/grid_resolution_data.txt"

write_frame_data(filePath, frame_data)
print(f"Grid resolution data for frame {currentFrame} written to file")

if name==‘main’: main()

Which gives us eg. :

Frame: 464, Grid Resolution: 56x56 Frame: 465, Grid Resolution: 56x56 Frame: 466, Grid Resolution: 52x52 Frame: 467, Grid Resolution: 36x36

I’d now like to change it so that we only write to the file when the grid resolution value changes. Essentially skipping frames where no change occurs

ChatGPT

To modify your script so that it only writes to the file when the grid resolution changes, you’ll need to keep track of the previous frame’s grid resolution and compare it with the current frame’s resolution. If they differ, then write the data to the file. Here’s how you can implement this:

1. Global Variable for Previous Resolution:

   • You will need a global variable to store the grid resolution of the previous frame. This variable needs to be declared outside of your main function.

2. Compare Current and Previous Resolutions:

   • In the main function, before writing to the file, compare the current grid resolution with the previous one. If they are different, then write to the file and update the global variable with the current resolution.

3. Initialize the Previous Resolution:

   • The first time your script runs, there won’t be a “previous frame” resolution. You can handle this by initializing the global variable with a value that ensures the first frame’s data gets written (for example, an impossible resolution like (-1, -1)).

Here’s your updated script with these changes:

import c4d

# Global variable to store the previous frame's grid resolution
previous_resolution = (-1, -1)

def write_frame_data(filePath, frame_data):
    with open(filePath, "a") as file:
        file.write(frame_data + "\n")

def main():
    global previous_resolution

    matrix_object = op.GetObject()
    if not matrix_object:
        print("Object not found")
        return

    grid_resolution = matrix_object[c4d.MG_GRID_RESOLUTION]
    if grid_resolution is None:
        print("Grid resolution data not found")
        return

    x_count = int(grid_resolution.x)
    z_count = int(grid_resolution.z)

    # Check if the grid resolution has changed since the last frame
    if (x_count, z_count) != previous_resolution:
        currentFrame = doc.GetTime().GetFrame(doc.GetFps())
        frame_data = f"Frame: {currentFrame}, Grid Resolution: {x_count}x{z_count}"

        filePath = "H:/My Drive/02_Projects/41_SPTF_FCBNY Spotify/00_Research and Development/C4D/Sketching/231122 Write Values from C4D/Written/grid_resolution_data.txt"

        write_frame_data(filePath, frame_data)
        print(f"Grid resolution data for frame {currentFrame} written to file")

        # Update the previous resolution
        previous_resolution = (x_count, z_count)

if __name__=='__main__':
    main()

This script will now only write the frame data to the file when the grid resolution changes, reducing the amount of redundant data in your file.