17 files changed, 545 insertions, 252 deletions
diff --git a/modules/api/api.py b/modules/api/api.py
index 48a70a44..2103709b 100644
--- a/modules/api/api.py
+++ b/modules/api/api.py
@@ -11,10 +11,10 @@ from fastapi.security import HTTPBasic, HTTPBasicCredentials
 from secrets import compare_digest
 
 import modules.shared as shared
-from modules import sd_samplers, deepbooru, sd_hijack
+from modules import sd_samplers, deepbooru, sd_hijack, images
 from modules.api.models import *
 from modules.processing import StableDiffusionProcessingTxt2Img, StableDiffusionProcessingImg2Img, process_images
-from modules.extras import run_extras, run_pnginfo
+from modules.extras import run_extras
 from modules.textual_inversion.textual_inversion import create_embedding, train_embedding
 from modules.textual_inversion.preprocess import preprocess
 from modules.hypernetworks.hypernetwork import create_hypernetwork, train_hypernetwork
@@ -233,9 +233,17 @@ class Api:
         if(not req.image.strip()):
             return PNGInfoResponse(info="")
 
-        result = run_pnginfo(decode_base64_to_image(req.image.strip()))
+        image = decode_base64_to_image(req.image.strip())
+        if image is None:
+            return PNGInfoResponse(info="")
+
+        geninfo, items = images.read_info_from_image(image)
+        if geninfo is None:
+            geninfo = ""
+
+        items = {**{'parameters': geninfo}, **items}
 
-        return PNGInfoResponse(info=result[1])
+        return PNGInfoResponse(info=geninfo, items=items)
 
     def progressapi(self, req: ProgressRequest = Depends()):
         # copy from check_progress_call of ui.py
diff --git a/modules/api/models.py b/modules/api/models.py
index 4a632c68..d8198a27 100644
--- a/modules/api/models.py
+++ b/modules/api/models.py
@@ -157,7 +157,8 @@ class PNGInfoRequest(BaseModel):
     image: str = Field(title="Image", description="The base64 encoded PNG image")
 
 class PNGInfoResponse(BaseModel):
-    info: str = Field(title="Image info", description="A string with all the info the image had")
+    info: str = Field(title="Image info", description="A string with the parameters used to generate the image")
+    items: dict = Field(title="Items", description="An object containing all the info the image had")
 
 class ProgressRequest(BaseModel):
     skip_current_image: bool = Field(default=False, title="Skip current image", description="Skip current image serialization")
@@ -258,4 +259,4 @@ class EmbeddingItem(BaseModel):
 
 class EmbeddingsResponse(BaseModel):
     loaded: Dict[str, EmbeddingItem] = Field(title="Loaded", description="Embeddings loaded for the current model")
-    skipped: Dict[str, EmbeddingItem] = Field(title="Skipped", description="Embeddings skipped for the current model (likely due to architecture incompatibility)")
-\ No newline at end of file
+    skipped: Dict[str, EmbeddingItem] = Field(title="Skipped", description="Embeddings skipped for the current model (likely due to architecture incompatibility)")
diff --git a/modules/devices.py b/modules/devices.py
index 800510b7..caeb0276 100644
--- a/modules/devices.py
+++ b/modules/devices.py
@@ -133,8 +133,26 @@ def numpy_fix(self, *args, **kwargs):
     return orig_tensor_numpy(self, *args, **kwargs)
 
 
-# PyTorch 1.13 doesn't need these fixes but unfortunately is slower and has regressions that prevent training from working
-if has_mps() and version.parse(torch.__version__) < version.parse("1.13"):
-    torch.Tensor.to = tensor_to_fix
-    torch.nn.functional.layer_norm = layer_norm_fix
-    torch.Tensor.numpy = numpy_fix
+# MPS workaround for https://github.com/pytorch/pytorch/issues/89784
+orig_cumsum = torch.cumsum
+orig_Tensor_cumsum = torch.Tensor.cumsum
+def cumsum_fix(input, cumsum_func, *args, **kwargs):
+    if input.device.type == 'mps':
+        output_dtype = kwargs.get('dtype', input.dtype)
+        if any(output_dtype == broken_dtype for broken_dtype in [torch.bool, torch.int8, torch.int16, torch.int64]):
+            return cumsum_func(input.cpu(), *args, **kwargs).to(input.device)
+    return cumsum_func(input, *args, **kwargs)
+
+
+if has_mps():
+    if version.parse(torch.__version__) < version.parse("1.13"):
+        # PyTorch 1.13 doesn't need these fixes but unfortunately is slower and has regressions that prevent training from working
+        torch.Tensor.to = tensor_to_fix
+        torch.nn.functional.layer_norm = layer_norm_fix
+        torch.Tensor.numpy = numpy_fix
+    elif version.parse(torch.__version__) > version.parse("1.13.1"):
+        if not torch.Tensor([1,2]).to(torch.device("mps")).equal(torch.Tensor([1,1]).to(torch.device("mps")).cumsum(0, dtype=torch.int16)):
+            torch.cumsum = lambda input, *args, **kwargs: ( cumsum_fix(input, orig_cumsum, *args, **kwargs) )
+            torch.Tensor.cumsum = lambda self, *args, **kwargs: ( cumsum_fix(self, orig_Tensor_cumsum, *args, **kwargs) )
+        orig_narrow = torch.narrow
+        torch.narrow = lambda *args, **kwargs: ( orig_narrow(*args, **kwargs).clone() )
diff --git a/modules/hypernetworks/hypernetwork.py b/modules/hypernetworks/hypernetwork.py
index 6a9b1398..b0cfbe71 100644
--- a/modules/hypernetworks/hypernetwork.py
+++ b/modules/hypernetworks/hypernetwork.py
@@ -13,7 +13,7 @@ import tqdm
 from einops import rearrange, repeat
 from ldm.util import default
 from modules import devices, processing, sd_models, shared, sd_samplers
-from modules.textual_inversion import textual_inversion
+from modules.textual_inversion import textual_inversion, logging
 from modules.textual_inversion.learn_schedule import LearnRateScheduler
 from torch import einsum
 from torch.nn.init import normal_, xavier_normal_, xavier_uniform_, kaiming_normal_, kaiming_uniform_, zeros_
@@ -457,7 +457,14 @@ def train_hypernetwork(hypernetwork_name, learn_rate, batch_size, gradient_step,
     pin_memory = shared.opts.pin_memory
 
     ds = modules.textual_inversion.dataset.PersonalizedBase(data_root=data_root, width=training_width, height=training_height, repeats=shared.opts.training_image_repeats_per_epoch, placeholder_token=hypernetwork_name, model=shared.sd_model, cond_model=shared.sd_model.cond_stage_model, device=devices.device, template_file=template_file, include_cond=True, batch_size=batch_size, gradient_step=gradient_step, shuffle_tags=shuffle_tags, tag_drop_out=tag_drop_out, latent_sampling_method=latent_sampling_method)
-    
+
+    if shared.opts.save_training_settings_to_txt:
+        saved_params = dict(
+            model_name=checkpoint.model_name, model_hash=checkpoint.hash, num_of_dataset_images=len(ds),
+            **{field: getattr(hypernetwork, field) for field in ['layer_structure', 'activation_func', 'weight_init', 'add_layer_norm', 'use_dropout', ]}
+        )
+        logging.save_settings_to_file(log_directory, {**saved_params, **locals()})
+
     latent_sampling_method = ds.latent_sampling_method
 
     dl = modules.textual_inversion.dataset.PersonalizedDataLoader(ds, latent_sampling_method=latent_sampling_method, batch_size=ds.batch_size, pin_memory=pin_memory)
diff --git a/modules/processing.py b/modules/processing.py
index 7e853287..82157bc9 100644
--- a/modules/processing.py
+++ b/modules/processing.py
@@ -50,9 +50,9 @@ def apply_color_correction(correction, original_image):
         correction,
         channel_axis=2
     ), cv2.COLOR_LAB2RGB).astype("uint8"))
-    
+
     image = blendLayers(image, original_image, BlendType.LUMINOSITY)
-    
+
     return image
 
 
@@ -466,9 +466,15 @@ def process_images(p: StableDiffusionProcessing) -> Processed:
     try:
         for k, v in p.override_settings.items():
             setattr(opts, k, v)
-            if k == 'sd_hypernetwork': shared.reload_hypernetworks()  # make onchange call for changing hypernet
-            if k == 'sd_model_checkpoint': sd_models.reload_model_weights()  # make onchange call for changing SD model
-            if k == 'sd_vae': sd_vae.reload_vae_weights()  # make onchange call for changing VAE
+            if k == 'sd_hypernetwork':
+                shared.reload_hypernetworks()  # make onchange call for changing hypernet
+
+            if k == 'sd_model_checkpoint':
+                sd_models.reload_model_weights()  # make onchange call for changing SD model
+                p.sd_model = shared.sd_model
+
+            if k == 'sd_vae':
+                sd_vae.reload_vae_weights()  # make onchange call for changing VAE
 
         res = process_images_inner(p)
 
@@ -538,6 +544,29 @@ def process_images_inner(p: StableDiffusionProcessing) -> Processed:
     infotexts = []
     output_images = []
 
+    cached_uc = [None, None]
+    cached_c = [None, None]
+
+    def get_conds_with_caching(function, required_prompts, steps, cache):
+        """
+        Returns the result of calling function(shared.sd_model, required_prompts, steps)
+        using a cache to store the result if the same arguments have been used before.
+
+        cache is an array containing two elements. The first element is a tuple
+        representing the previously used arguments, or None if no arguments
+        have been used before. The second element is where the previously
+        computed result is stored.
+        """
+
+        if cache[0] is not None and (required_prompts, steps) == cache[0]:
+            return cache[1]
+
+        with devices.autocast():
+            cache[1] = function(shared.sd_model, required_prompts, steps)
+
+        cache[0] = (required_prompts, steps)
+        return cache[1]
+
     with torch.no_grad(), p.sd_model.ema_scope():
         with devices.autocast():
             p.init(p.all_prompts, p.all_seeds, p.all_subseeds)
@@ -565,9 +594,8 @@ def process_images_inner(p: StableDiffusionProcessing) -> Processed:
             if p.scripts is not None:
                 p.scripts.process_batch(p, batch_number=n, prompts=prompts, seeds=seeds, subseeds=subseeds)
 
-            with devices.autocast():
-                uc = prompt_parser.get_learned_conditioning(shared.sd_model, negative_prompts, p.steps)
-                c = prompt_parser.get_multicond_learned_conditioning(shared.sd_model, prompts, p.steps)
+            uc = get_conds_with_caching(prompt_parser.get_learned_conditioning, negative_prompts, p.steps, cached_uc)
+            c = get_conds_with_caching(prompt_parser.get_multicond_learned_conditioning, prompts, p.steps, cached_c)
 
             if len(model_hijack.comments) > 0:
                 for comment in model_hijack.comments:
@@ -683,7 +711,6 @@ class StableDiffusionProcessingTxt2Img(StableDiffusionProcessing):
         self.truncate_x = 0
         self.truncate_y = 0
 
-
     def init(self, all_prompts, all_seeds, all_subseeds):
         if self.enable_hr:
             if self.hr_resize_x == 0 and self.hr_resize_y == 0:
diff --git a/modules/script_callbacks.py b/modules/script_callbacks.py
index de69fd9f..608c5300 100644
--- a/modules/script_callbacks.py
+++ b/modules/script_callbacks.py
@@ -71,6 +71,7 @@ callback_map = dict(
     callbacks_before_component=[],
     callbacks_after_component=[],
     callbacks_image_grid=[],
+    callbacks_script_unloaded=[],
 )
 
 
@@ -171,6 +172,14 @@ def image_grid_callback(params: ImageGridLoopParams):
             report_exception(c, 'image_grid')
 
 
+def script_unloaded_callback():
+    for c in reversed(callback_map['callbacks_script_unloaded']):
+        try:
+            c.callback()
+        except Exception:
+            report_exception(c, 'script_unloaded')
+
+
 def add_callback(callbacks, fun):
     stack = [x for x in inspect.stack() if x.filename != __file__]
     filename = stack[0].filename if len(stack) > 0 else 'unknown file'
@@ -202,7 +211,7 @@ def on_app_started(callback):
 
 def on_model_loaded(callback):
     """register a function to be called when the stable diffusion model is created; the model is
-    passed as an argument"""
+    passed as an argument; this function is also called when the script is reloaded. """
     add_callback(callback_map['callbacks_model_loaded'], callback)
 
 
@@ -279,3 +288,10 @@ def on_image_grid(callback):
        - params: ImageGridLoopParams - parameters to be used for grid creation. Can be modified.
     """
     add_callback(callback_map['callbacks_image_grid'], callback)
+
+
+def on_script_unloaded(callback):
+    """register a function to be called before the script is unloaded. Any hooks/hijacks/monkeying about that
+    the script did should be reverted here"""
+
+    add_callback(callback_map['callbacks_script_unloaded'], callback)
diff --git a/modules/scripts.py b/modules/scripts.py
index 722f8685..35164093 100644
--- a/modules/scripts.py
+++ b/modules/scripts.py
@@ -1,4 +1,5 @@
 import os
+import re
 import sys
 import traceback
 from collections import namedtuple
@@ -128,6 +129,15 @@ class Script:
         """unused"""
         return ""
 
+    def elem_id(self, item_id):
+        """helper function to generate id for a HTML element, constructs final id out of script name, tab and user-supplied item_id"""
+
+        need_tabname = self.show(True) == self.show(False)
+        tabname = ('img2img' if self.is_img2img else 'txt2txt') + "_" if need_tabname else ""
+        title = re.sub(r'[^a-z_0-9]', '', re.sub(r'\s', '_', self.title().lower()))
+
+        return f'script_{tabname}{title}_{item_id}'
+
 
 current_basedir = paths.script_path
 
@@ -280,7 +290,6 @@ class ScriptRunner:
             script.group = group
 
         dropdown = gr.Dropdown(label="Script", elem_id="script_list", choices=["None"] + self.titles, value="None", type="index")
-        dropdown.save_to_config = True
         inputs[0] = dropdown
 
         for script in self.selectable_scripts:
diff --git a/modules/sd_hijack.py b/modules/sd_hijack.py
index bd101e5b..cfdb09d6 100644
--- a/modules/sd_hijack.py
+++ b/modules/sd_hijack.py
@@ -147,10 +147,10 @@ class StableDiffusionModelHijack:
     def clear_comments(self):
         self.comments = []
 
-    def tokenize(self, text):
-        _, remade_batch_tokens, _, _, _, token_count = self.clip.process_text([text])
+    def get_prompt_lengths(self, text):
+        _, token_count = self.clip.process_texts([text])
 
-        return remade_batch_tokens[0], token_count, sd_hijack_clip.get_target_prompt_token_count(token_count)
+        return token_count, self.clip.get_target_prompt_token_count(token_count)
 
 
 class EmbeddingsWithFixes(torch.nn.Module):
diff --git a/modules/sd_hijack_clip.py b/modules/sd_hijack_clip.py
index ca92b142..5520c9b2 100644
--- a/modules/sd_hijack_clip.py
+++ b/modules/sd_hijack_clip.py
@@ -1,30 +1,89 @@
 import math
+from collections import namedtuple
 
 import torch
 
-from modules import prompt_parser, devices
+from modules import prompt_parser, devices, sd_hijack
 from modules.shared import opts
 
-def get_target_prompt_token_count(token_count):
-    return math.ceil(max(token_count, 1) / 75) * 75
+
+class PromptChunk:
+    """
+    This object contains token ids, weight (multipliers:1.4) and textual inversion embedding info for a chunk of prompt.
+    If a prompt is short, it is represented by one PromptChunk, otherwise, multiple are necessary.
+    Each PromptChunk contains an exact amount of tokens - 77, which includes one for start and end token,
+    so just 75 tokens from prompt.
+    """
+
+    def __init__(self):
+        self.tokens = []
+        self.multipliers = []
+        self.fixes = []
+
+
+PromptChunkFix = namedtuple('PromptChunkFix', ['offset', 'embedding'])
+"""An object of this type is a marker showing that textual inversion embedding's vectors have to placed at offset in the prompt
+chunk. Thos objects are found in PromptChunk.fixes and, are placed into FrozenCLIPEmbedderWithCustomWordsBase.hijack.fixes, and finally
+are applied by sd_hijack.EmbeddingsWithFixes's forward function."""
 
 
 class FrozenCLIPEmbedderWithCustomWordsBase(torch.nn.Module):
+    """A pytorch module that is a wrapper for FrozenCLIPEmbedder module. it enhances FrozenCLIPEmbedder, making it possible to
+    have unlimited prompt length and assign weights to tokens in prompt.
+    """
+
     def __init__(self, wrapped, hijack):
         super().__init__()
+
         self.wrapped = wrapped
-        self.hijack = hijack
+        """Original FrozenCLIPEmbedder module; can also be FrozenOpenCLIPEmbedder or xlmr.BertSeriesModelWithTransformation,
+        depending on model."""
+
+        self.hijack: sd_hijack.StableDiffusionModelHijack = hijack
+        self.chunk_length = 75
+
+    def empty_chunk(self):
+        """creates an empty PromptChunk and returns it"""
+
+        chunk = PromptChunk()
+        chunk.tokens = [self.id_start] + [self.id_end] * (self.chunk_length + 1)
+        chunk.multipliers = [1.0] * (self.chunk_length + 2)
+        return chunk
+
+    def get_target_prompt_token_count(self, token_count):
+        """returns the maximum number of tokens a prompt of a known length can have before it requires one more PromptChunk to be represented"""
+
+        return math.ceil(max(token_count, 1) / self.chunk_length) * self.chunk_length
 
     def tokenize(self, texts):
+        """Converts a batch of texts into a batch of token ids"""
+
         raise NotImplementedError
 
     def encode_with_transformers(self, tokens):
+        """
+        converts a batch of token ids (in python lists) into a single tensor with numeric respresentation of those tokens;
+        All python lists with tokens are assumed to have same length, usually 77.
+        if input is a list with B elements and each element has T tokens, expected output shape is (B, T, C), where C depends on
+        model - can be 768 and 1024.
+        Among other things, this call will read self.hijack.fixes, apply it to its inputs, and clear it (setting it to None).
+        """
+
         raise NotImplementedError
 
     def encode_embedding_init_text(self, init_text, nvpt):
+        """Converts text into a tensor with this text's tokens' embeddings. Note that those are embeddings before they are passed through
+        transformers. nvpt is used as a maximum length in tokens. If text produces less teokens than nvpt, only this many is returned."""
+
         raise NotImplementedError
 
-    def tokenize_line(self, line, used_custom_terms, hijack_comments):
+    def tokenize_line(self, line):
+        """
+        this transforms a single prompt into a list of PromptChunk objects - as many as needed to
+        represent the prompt.
+        Returns the list and the total number of tokens in the prompt.
+        """
+
         if opts.enable_emphasis:
             parsed = prompt_parser.parse_prompt_attention(line)
         else:
@@ -32,205 +91,152 @@ class FrozenCLIPEmbedderWithCustomWordsBase(torch.nn.Module):
 
         tokenized = self.tokenize([text for text, _ in parsed])
 
-        fixes = []
-        remade_tokens = []
-        multipliers = []
+        chunks = []
+        chunk = PromptChunk()
+        token_count = 0
         last_comma = -1
 
-        for tokens, (text, weight) in zip(tokenized, parsed):
-            i = 0
-            while i < len(tokens):
-                token = tokens[i]
+        def next_chunk():
+            """puts current chunk into the list of results and produces the next one - empty"""
+            nonlocal token_count
+            nonlocal last_comma
+            nonlocal chunk
 
-                embedding, embedding_length_in_tokens = self.hijack.embedding_db.find_embedding_at_position(tokens, i)
+            token_count += len(chunk.tokens)
+            to_add = self.chunk_length - len(chunk.tokens)
+            if to_add > 0:
+                chunk.tokens += [self.id_end] * to_add
+                chunk.multipliers += [1.0] * to_add
+
+            chunk.tokens = [self.id_start] + chunk.tokens + [self.id_end]
+            chunk.multipliers = [1.0] + chunk.multipliers + [1.0]
+
+            last_comma = -1
+            chunks.append(chunk)
+            chunk = PromptChunk()
+
+        for tokens, (text, weight) in zip(tokenized, parsed):
+            position = 0
+            while position < len(tokens):
+                token = tokens[position]
 
                 if token == self.comma_token:
-                    last_comma = len(remade_tokens)
-                elif opts.comma_padding_backtrack != 0 and max(len(remade_tokens), 1) % 75 == 0 and last_comma != -1 and len(remade_tokens) - last_comma <= opts.comma_padding_backtrack:
-                    last_comma += 1
-                    reloc_tokens = remade_tokens[last_comma:]
-                    reloc_mults = multipliers[last_comma:]
+                    last_comma = len(chunk.tokens)
+
+                # this is when we are at the end of alloted 75 tokens for the current chunk, and the current token is not a comma. opts.comma_padding_backtrack
+                # is a setting that specifies that if there is a comma nearby, the text after the comma should be moved out of this chunk and into the next.
+                elif opts.comma_padding_backtrack != 0 and len(chunk.tokens) == self.chunk_length and last_comma != -1 and len(chunk.tokens) - last_comma <= opts.comma_padding_backtrack:
+                    break_location = last_comma + 1
 
-                    remade_tokens = remade_tokens[:last_comma]
-                    length = len(remade_tokens)
+                    reloc_tokens = chunk.tokens[break_location:]
+                    reloc_mults = chunk.multipliers[break_location:]
 
-                    rem = int(math.ceil(length / 75)) * 75 - length
-                    remade_tokens += [self.id_end] * rem + reloc_tokens
-                    multipliers = multipliers[:last_comma] + [1.0] * rem + reloc_mults
+                    chunk.tokens = chunk.tokens[:break_location]
+                    chunk.multipliers = chunk.multipliers[:break_location]
 
+                    next_chunk()
+                    chunk.tokens = reloc_tokens
+                    chunk.multipliers = reloc_mults
+
+                if len(chunk.tokens) == self.chunk_length:
+                    next_chunk()
+
+                embedding, embedding_length_in_tokens = self.hijack.embedding_db.find_embedding_at_position(tokens, position)
                 if embedding is None:
-                    remade_tokens.append(token)
-                    multipliers.append(weight)
-                    i += 1
-                else:
-                    emb_len = int(embedding.vec.shape[0])
-                    iteration = len(remade_tokens) // 75
-                    if (len(remade_tokens) + emb_len) // 75 != iteration:
-                        rem = (75 * (iteration + 1) - len(remade_tokens))
-                        remade_tokens += [self.id_end] * rem
-                        multipliers += [1.0] * rem
-                        iteration += 1
-                    fixes.append((iteration, (len(remade_tokens) % 75, embedding)))
-                    remade_tokens += [0] * emb_len
-                    multipliers += [weight] * emb_len
-                    used_custom_terms.append((embedding.name, embedding.checksum()))
-                    i += embedding_length_in_tokens
-
-        token_count = len(remade_tokens)
-        prompt_target_length = get_target_prompt_token_count(token_count)
-        tokens_to_add = prompt_target_length - len(remade_tokens)
-
-        remade_tokens = remade_tokens + [self.id_end] * tokens_to_add
-        multipliers = multipliers + [1.0] * tokens_to_add
-
-        return remade_tokens, fixes, multipliers, token_count
-
-    def process_text(self, texts):
-        used_custom_terms = []
-        remade_batch_tokens = []
-        hijack_comments = []
-        hijack_fixes = []
+                    chunk.tokens.append(token)
+                    chunk.multipliers.append(weight)
+                    position += 1
+                    continue
+
+                emb_len = int(embedding.vec.shape[0])
+                if len(chunk.tokens) + emb_len > self.chunk_length:
+                    next_chunk()
+
+                chunk.fixes.append(PromptChunkFix(len(chunk.tokens), embedding))
+
+                chunk.tokens += [0] * emb_len
+                chunk.multipliers += [weight] * emb_len
+                position += embedding_length_in_tokens
+
+        if len(chunk.tokens) > 0 or len(chunks) == 0:
+            next_chunk()
+
+        return chunks, token_count
+
+    def process_texts(self, texts):
+        """
+        Accepts a list of texts and calls tokenize_line() on each, with cache. Returns the list of results and maximum
+        length, in tokens, of all texts.
+        """
+
         token_count = 0
 
         cache = {}
-        batch_multipliers = []
+        batch_chunks = []
         for line in texts:
             if line in cache:
-                remade_tokens, fixes, multipliers = cache[line]
+                chunks = cache[line]
             else:
-                remade_tokens, fixes, multipliers, current_token_count = self.tokenize_line(line, used_custom_terms, hijack_comments)
+                chunks, current_token_count = self.tokenize_line(line)
                 token_count = max(current_token_count, token_count)
 
-                cache[line] = (remade_tokens, fixes, multipliers)
+                cache[line] = chunks
 
-            remade_batch_tokens.append(remade_tokens)
-            hijack_fixes.append(fixes)
-            batch_multipliers.append(multipliers)
+            batch_chunks.append(chunks)
 
-        return batch_multipliers, remade_batch_tokens, used_custom_terms, hijack_comments, hijack_fixes, token_count
+        return batch_chunks, token_count
 
-    def process_text_old(self, texts):
-        id_start = self.id_start
-        id_end = self.id_end
-        maxlen = self.wrapped.max_length  # you get to stay at 77
-        used_custom_terms = []
-        remade_batch_tokens = []
-        hijack_comments = []
-        hijack_fixes = []
-        token_count = 0
+    def forward(self, texts):
+        """
+        Accepts an array of texts; Passes texts through transformers network to create a tensor with numerical representation of those texts.
+        Returns a tensor with shape of (B, T, C), where B is length of the array; T is length, in tokens, of texts (including padding) - T will
+        be a multiple of 77; and C is dimensionality of each token - for SD1 it's 768, and for SD2 it's 1024.
+        An example shape returned by this function can be: (2, 77, 768).
+        Webui usually sends just one text at a time through this function - the only time when texts is an array with more than one elemenet
+        is when you do prompt editing: "a picture of a [cat:dog:0.4] eating ice cream"
+        """
 
-        cache = {}
-        batch_tokens = self.tokenize(texts)
-        batch_multipliers = []
-        for tokens in batch_tokens:
-            tuple_tokens = tuple(tokens)
+        if opts.use_old_emphasis_implementation:
+            import modules.sd_hijack_clip_old
+            return modules.sd_hijack_clip_old.forward_old(self, texts)
 
-            if tuple_tokens in cache:
-                remade_tokens, fixes, multipliers = cache[tuple_tokens]
-            else:
-                fixes = []
-                remade_tokens = []
-                multipliers = []
-                mult = 1.0
-
-                i = 0
-                while i < len(tokens):
-                    token = tokens[i]
-
-                    embedding, embedding_length_in_tokens = self.hijack.embedding_db.find_embedding_at_position(tokens, i)
-
-                    mult_change = self.token_mults.get(token) if opts.enable_emphasis else None
-                    if mult_change is not None:
-                        mult *= mult_change
-                        i += 1
-                    elif embedding is None:
-                        remade_tokens.append(token)
-                        multipliers.append(mult)
-                        i += 1
-                    else:
-                        emb_len = int(embedding.vec.shape[0])
-                        fixes.append((len(remade_tokens), embedding))
-                        remade_tokens += [0] * emb_len
-                        multipliers += [mult] * emb_len
-                        used_custom_terms.append((embedding.name, embedding.checksum()))
-                        i += embedding_length_in_tokens
-
-                if len(remade_tokens) > maxlen - 2:
-                    vocab = {v: k for k, v in self.wrapped.tokenizer.get_vocab().items()}
-                    ovf = remade_tokens[maxlen - 2:]
-                    overflowing_words = [vocab.get(int(x), "") for x in ovf]
-                    overflowing_text = self.wrapped.tokenizer.convert_tokens_to_string(''.join(overflowing_words))
-                    hijack_comments.append(f"Warning: too many input tokens; some ({len(overflowing_words)}) have been truncated:\n{overflowing_text}\n")
-
-                token_count = len(remade_tokens)
-                remade_tokens = remade_tokens + [id_end] * (maxlen - 2 - len(remade_tokens))
-                remade_tokens = [id_start] + remade_tokens[0:maxlen - 2] + [id_end]
-                cache[tuple_tokens] = (remade_tokens, fixes, multipliers)
-
-            multipliers = multipliers + [1.0] * (maxlen - 2 - len(multipliers))
-            multipliers = [1.0] + multipliers[0:maxlen - 2] + [1.0]
-
-            remade_batch_tokens.append(remade_tokens)
-            hijack_fixes.append(fixes)
-            batch_multipliers.append(multipliers)
-        return batch_multipliers, remade_batch_tokens, used_custom_terms, hijack_comments, hijack_fixes, token_count
-
-    def forward(self, text):
-        use_old = opts.use_old_emphasis_implementation
-        if use_old:
-            batch_multipliers, remade_batch_tokens, used_custom_terms, hijack_comments, hijack_fixes, token_count = self.process_text_old(text)
-        else:
-            batch_multipliers, remade_batch_tokens, used_custom_terms, hijack_comments, hijack_fixes, token_count = self.process_text(text)
-
-        self.hijack.comments += hijack_comments
-
-        if len(used_custom_terms) > 0:
-            self.hijack.comments.append("Used embeddings: " + ", ".join([f'{word} [{checksum}]' for word, checksum in used_custom_terms]))
-
-        if use_old:
-            self.hijack.fixes = hijack_fixes
-            return self.process_tokens(remade_batch_tokens, batch_multipliers)
-
-        z = None
-        i = 0
-        while max(map(len, remade_batch_tokens)) != 0:
-            rem_tokens = [x[75:] for x in remade_batch_tokens]
-            rem_multipliers = [x[75:] for x in batch_multipliers]
-
-            self.hijack.fixes = []
-            for unfiltered in hijack_fixes:
-                fixes = []
-                for fix in unfiltered:
-                    if fix[0] == i:
-                        fixes.append(fix[1])
-                self.hijack.fixes.append(fixes)
-
-            tokens = []
-            multipliers = []
-            for j in range(len(remade_batch_tokens)):
-                if len(remade_batch_tokens[j]) > 0:
-                    tokens.append(remade_batch_tokens[j][:75])
-                    multipliers.append(batch_multipliers[j][:75])
-                else:
-                    tokens.append([self.id_end] * 75)
-                    multipliers.append([1.0] * 75)
-
-            z1 = self.process_tokens(tokens, multipliers)
-            z = z1 if z is None else torch.cat((z, z1), axis=-2)
-
-            remade_batch_tokens = rem_tokens
-            batch_multipliers = rem_multipliers
-            i += 1
+        batch_chunks, token_count = self.process_texts(texts)
 
-        return z
+        used_embeddings = {}
+        chunk_count = max([len(x) for x in batch_chunks])
 
-    def process_tokens(self, remade_batch_tokens, batch_multipliers):
-        if not opts.use_old_emphasis_implementation:
-            remade_batch_tokens = [[self.id_start] + x[:75] + [self.id_end] for x in remade_batch_tokens]
-            batch_multipliers = [[1.0] + x[:75] + [1.0] for x in batch_multipliers]
+        zs = []
+        for i in range(chunk_count):
+            batch_chunk = [chunks[i] if i < len(chunks) else self.empty_chunk() for chunks in batch_chunks]
+
+            tokens = [x.tokens for x in batch_chunk]
+            multipliers = [x.multipliers for x in batch_chunk]
+            self.hijack.fixes = [x.fixes for x in batch_chunk]
 
+            for fixes in self.hijack.fixes:
+                for position, embedding in fixes:
+                    used_embeddings[embedding.name] = embedding
+
+            z = self.process_tokens(tokens, multipliers)
+            zs.append(z)
+
+        if len(used_embeddings) > 0:
+            embeddings_list = ", ".join([f'{name} [{embedding.checksum()}]' for name, embedding in used_embeddings.items()])
+            self.hijack.comments.append(f"Used embeddings: {embeddings_list}")
+
+        return torch.hstack(zs)
+
+    def process_tokens(self, remade_batch_tokens, batch_multipliers):
+        """
+        sends one single prompt chunk to be encoded by transformers neural network.
+        remade_batch_tokens is a batch of tokens - a list, where every element is a list of tokens; usually
+        there are exactly 77 tokens in the list. batch_multipliers is the same but for multipliers instead of tokens.
+        Multipliers are used to give more or less weight to the outputs of transformers network. Each multiplier
+        corresponds to one token.
+        """
         tokens = torch.asarray(remade_batch_tokens).to(devices.device)
 
+        # this is for SD2: SD1 uses the same token for padding and end of text, while SD2 uses different ones.
         if self.id_end != self.id_pad:
             for batch_pos in range(len(remade_batch_tokens)):