PHASE 1: VISUAL DECONSTRUCTION - **Fabric Physics:** The source garment is a structured white cotton or cotton-poplin blend. It possesses a "crisp" rigidity, meaning it does not cling like jersey knit but holds its shape around the collar and shoulders. It has a matte finish with low specularity (no shine), diffusing light evenly. - **Key Features:** - **Sleeves:** Short sleeves ending mid-bicep (Crucial: This differs from the user's current long sleeves). - **Pocket:** Single patch pocket on the wearer's left chest. - **Placket:** Standard front button closure with white buttons. - **Collar:** Classic point collar, stiffened interfacing. - **Hem:** Curved "shirttail" hemline designed to be worn untucked. PHASE 2: FIT & DRAPE SIMULATION - **Body Mapping:** - **Shoulders:** The shirt must align with the user's acromion points. The fabric should drape vertically from the chest apex, creating a slight "air gap" at the waist to indicate the structured cotton material. - **Sleeve Transition:** Since the user is wearing long sleeves and the source is short-sleeved, the simulation must generatively inpaint the user's forearms and elbows with skin tone and hair texture matching his face and hands. The sleeves should flare slightly away from the arm, not squeeze the bicep. - **Hemline Interaction:** The shirt should hang *over* the waistband of the user's beige trousers, casting a drop shadow onto the pants. - **Occlusion Handling:** - **Beard:** The user's beard overlaps the neck area; the new collar must sit comfortably *behind/under* the beard, not clip through it. - **Hands:** The user's hands are visible at the hips; ensure the shirt hem or side seams do not render over the thumbs or wrists. PHASE 3: ENVIRONMENT & LIGHTING - **Light Match:** The user's environment has soft, diffuse indoor lighting coming from the viewer's left (casting a shadow on the wall to the viewer's right). The new white shirt must exhibit self-shadowing on the right side of the torso (away from the light source) and cast a shadow onto the neck and the beige pants. - **Color Calibration:** The source image is "studio white" (high brightness). This must be toned down (exposure reduction) and color-graded with a slight warm/yellow tint to match the ambient room temperature of the user image. Grain/noise must be added to the pristine white fabric to match the ISO grain of the user photo. PHASE 4: IDENTITY PROTECTION - **Facial Lock:** Absolute freeze on the user's face, beard, ears, and hair. The neck structure must be preserved but re-skinned where the old collar is removed. - **Body Integrity:** Maintain the user's shoulder width and torso volume. Do not slim the user to match the model's physique. The generative skin reconstruction on the arms must match the user's biometric proportions (no muscle enhancement or atrophy).