PHASE 1: VISUAL DECONSTRUCTION - **Fabric Physics:** The source garment is a lightweight cotton jersey or cotton-poly blend. It possesses a matte finish with low specular reflection. Unlike the user's current heavy knit sweater, the new fabric has high pliability and lower structural rigidity. It should exhibit micro-wrinkles rather than deep, heavy folds. - **Key Features:** The specific typography "YELLOW IMAGES.COM" centered on the chest, the "MEN'S T-SHIRT MOCKUP" badge on the right chest, and the vertical graphic on the left sleeve must be preserved without distortion. The contrasting dark orange crew neck ribbing and the specific hemline stitching are critical fidelity points. PHASE 2: FIT & DRAPE SIMULATION - **Body Mapping:** - **Right Arm (Raised):** The source is a short-sleeve T-shirt, while the user wears a long-sleeve sweater. The simulation must generate realistic skin texture for the user's now-exposed forearms. The right sleeve of the T-shirt must slide down toward the shoulder due to gravity, bunching slightly at the deltoid, while the hemline on the right side of the torso will lift upward, exposing the waistband of the trousers. - **Silhouette Correction:** The current sweater adds significant bulk. The simulation must estimate the underlying skin surface to ensure the T-shirt fits closer to the body, effectively reducing the torso volume to match the user's actual build, not the sweater's outline. - **Occlusion Handling:** The user's chin is tucked downwards; the collar of the new T-shirt must sit naturally under the chin without clipping into the jawline. The user's hands are clear of the torso, but the right arm's position dictates the fabric tension across the chest. PHASE 3: ENVIRONMENT & LIGHTING - **Light Match:** The scene features hard, direct sunlight coming from the upper right, casting sharp, distinct shadows (evident on the ground and railing). The T-shirt must render with high contrast: bright highlights on the right shoulder/chest and deep shadows on the left side of the torso. - **Color Calibration:** The source image is studio-lit with cool/neutral tones. The target environment is warm (sunlight) with significant blue ambient bounce from the lake and sky. The pink hue of the T-shirt must be color-graded to reflect the warm solar temperature while absorbing subtle blue tints in the shadowed folds to integrate with the outdoor atmosphere. PHASE 4: IDENTITY PROTECTION - **Facial Lock:** The user's facial features, specifically the beard, nose, and eyes (looking down), as well as the visible ear and hair, must remain completely frozen. The cap held in the hand must remain untouched. - **Body Integrity:** While the bulk of the old sweater must be removed, the user's underlying anatomical structure (shoulder width, chest breadth) must not be warped or artificially slimmed. The generated skin for the arms must match the skin tone of the face and feet perfectly.