PHASE 1: VISUAL DECONSTRUCTION - **Fabric Physics:** The source garment appears to be a lightweight chambray or cotton poplin with a matte finish. It possesses medium structural rigidity—enough to hold the shape of the collar, but soft enough to crease easily. It should scatter light diffusely (low specularity) rather than shine. The texture has a slight "denim-wash" unevenness that must be maintained. - **Key Features:** The all-over white palm tree print pattern must remain distinct and not blur during warping. The open "camp collar" structure, the contrast buttons down the placket, and the rolled/stitched hem on the short sleeves are critical geometric details to preserve. PHASE 2: FIT & DRAPE SIMULATION - **Body Mapping:** Due to the user's "arms crossed" pose, the simulation must calculate high compression across the chest and latissimus dorsi. The fabric must pull tight across the upper back and shoulders. Crucially, the short sleeves of the source garment will interact with the user's biceps; the fabric should bunch slightly at the armpit and flatten where the biceps press against the ribcage. - **Occlusion Handling:** This is a high-complexity occlusion scenario. The user's left and right forearms, hands, and the black wristwatch on the left wrist clearly overlap the torso area. The new garment must be rendered *behind* these elements. The grey long sleeves of the original user image must be completely masked out, ensuring no grey fabric "leaks" from under the new short sleeves. PHASE 3: ENVIRONMENT & LIGHTING - **Light Match:** The user is situated in a forest environment with dappled, high-contrast sunlight coming from the upper right (relative to the viewer). The source garment's flat, cool studio lighting must be relighted. The new shirt requires hard, cast shadows from the trees and self-shadowing from the user's crossed arms. - **Color Calibration:** The source shirt is a cool blue. To integrate into the user's scene, the color temperature of the shirt must be shifted warmer (increasing yellow/orange gamma) to match the ambient forest glow. The white palm trees should reflect the ambient warm sunlight, not pure white. PHASE 4: IDENTITY PROTECTION - **Facial Lock:** The user's entire head, including the specific jawline angle, hairstyle, and skin tone of the neck, must be frozen. - **Body Integrity:** The user's torso volume and posture (leaning against the tree) must remain unchanged. Do not warp the user's waist to match the source model's tapered fit; the garment must expand to fit the user's actual build.