PHASE 1: VISUAL DECONSTRUCTION - **Fabric Physics:** The source garment is a textured cotton-blend waffle knit or pique fabric with a matte finish. It possesses medium weight with low specular reflection; it should absorb light rather than shine. The structure is semi-rigid at the placket but soft across the torso. - **Key Features:** The Mandarin/band collar, the 3-button central placket (currently buttoned), the specific fabric texture grain, and the short sleeve cuffs must be preserved. The black pigment must retain its textural depth and not flatten into a solid void. PHASE 2: FIT & DRAPE SIMULATION - **Body Mapping:** The target user is rotated slightly to his right. The new garment must wrap around the pectorals and adhere to the trapezoids. Crucially, the source is short-sleeved while the user currently wears long sleeves; the simulation must generate accurate forearm skin texture and muscle definition for the exposed arms, terminating the sleeve mid-bicep. - **Occlusion Handling:** The user's right hand (fingers and knuckles) is currently gripping the lapel of the original garment. This is a critical occlusion zone. The new henley fabric must appear *behind* the fingers. The user's beard hair at the jawline must also layer over the new collar. PHASE 3: ENVIRONMENT & LIGHTING - **Light Match:** The target environment features strong, directional sunlight coming from the upper right, creating high-contrast shadows. The source garment (currently flat studio lit) must be relit to cast deep shadows on the left side of the torso and under the buttons/placket. - **Color Calibration:** The neutral black of the source shirt needs to accept the warm, yellow-hued bias of the sunlight. The black levels must be lifted slightly to simulate the scattering of intense outdoor light on textured cotton. PHASE 4: IDENTITY PROTECTION - **Facial Lock:** The user's entire head, including the specific grooming of the beard, hairstyle, and facial expression, must be frozen. - **Body Integrity:** The user's shoulder width, chest volume, and arm thickness must remain unaltered. No slimming filters allowed. The generated skin for the arms must match the skin tone of the face and neck perfectly.