# Pergola Mockup Prompts — v1, v2, and a proposed v3 Three attempts. Try v2 first; if it still goes freestanding, try v3. v1 (the one you used) is here for reference. --- ## v1 — what you already used (and what failed) > Replace the metal pergola on the left with a 14×12 redwood pergola extension in craftsman style. THREE redwood 4x4 posts (left, center, right) on square concrete footings, a pair of 2x8 sandwich beams across the top, NINE 2x6 rafters with a GENTLE 1:12 slope (12 inches of drop over 12 feet of run) from the new beams up to the existing wooden pavilion's 4x12 beam, TINTED GRAY (not clear) corrugated polycarbonate roofing panels with 2 panels per bay overlapped 12 inches in the middle, short 45-degree knee braces at every post-beam joint on the visible faces matching the existing pavilion's style, black decorative post bases visible at the bottom of each post, 2-foot decorative rafter tail overhang past the front (camera-facing) beam as exposed redwood. Match the existing pavilion's craftsman style. Same camera angle, lighting, and shadows as the photo. **Why it failed:** Saying "pergola extension" still triggers the freestanding 4-post template. The models deprioritize the structural details once they pattern-match. --- ## v2 — lead with the addition, never say "pergola" twice > This is a REDWOOD ADDITION attached to the existing wooden pavilion on the right. The wooden pavilion is FIXED and stays where it is. The metal pergola on the left will be removed and replaced. > > The new structure has THREE redwood 4x4 posts in a line, on the LEFT, CENTER, and RIGHT of a 14-foot-wide × 12-foot-deep footprint on the side AWAY from the pavilion. The posts are NOT connected at the top to each other directly — they support a pair of 2x8 sandwich beams that run PARALLEL TO THE PAVILION across all three post tops. > > Nine 2x6 rafters span FROM the top of those new sandwich beams UP TO the existing 4x12 beam face of the wooden pavilion on the right. The rafters slope upward away from the camera toward the pavilion. This is the only roof support — there is no fourth wall or fourth post. The structure is open on the LEFT side (the camera-facing side). > > The roof is TINTED GRAY corrugated polycarbonate, 2 panels per rafter bay overlapped 12 inches in the middle. Short 45-degree knee braces at every post-beam joint. Black decorative post bases visible at the bottom of each post. 2-foot decorative rafter tail overhang past the front (camera-facing) beam as exposed redwood. > > Match the existing pavilion's craftsman style. Same camera angle, lighting, and shadows as the photo. **What changed:** Frames the structure as an "addition attached to the pavilion" rather than a "pergola." Removes the word "pergola" from the body of the prompt. Explicitly says "no fourth wall or fourth post" to defeat the freestanding default. Names the slope direction ("upward away from the camera toward the pavilion") so flat-roof generators know which way to tilt. --- ## v3 — for when v2 still fails (use this as a "corrections" prompt after a bad v2 result) > The previous image you generated was wrong. It showed a freestanding structure with four corner posts. That is incorrect. This is what I actually need: > > 1. The new structure has ONLY THREE posts, not four. All three posts are on the SIDE OF THE STRUCTURE FARTHEST FROM THE PAVILION. There is no fourth post. The pavilion itself is the FOURTH SUPPORT. > 2. The roof rafters are ATTACHED TO THE PAVILION. They run from the new sandwich beams (atop the three posts) up to the pavilion's existing beam on the right. This is a one-way lean-to roof. > 3. The roof has a SLOPE. The low edge is on the LEFT (the new-post side). The high edge is on the RIGHT (where it meets the pavilion). The slope is 1:12, which means 1 inch of drop per 12 inches of run. Across the 12-foot depth, the roof drops 12 inches from high to low. > 4. EVERY post-beam joint has a 45-degree knee brace — a small triangular wooden block cut at 45° on both ends, screwed to the post and the beam. > 5. The post bases are black powder-coated metal — a visible saddle that wraps the bottom 6 inches of each post. > > Please regenerate with these corrections. **What this does:** Acknowledges the v2 failure, calls out the specific mistakes the model made, and restates each requirement as a numbered list (numbered lists get more attention from LLMs than prose). If v2 still produced a freestanding rectangle, v3 should pull it back. --- ## Why these prompts work better than v1 - **Word choice.** "Pergola" is the most triggering word. Models have been trained on millions of freestanding-pergola images, so the word alone flips the geometry before any other instruction can take effect. Replacing it with "redwood addition attached to a pavilion" breaks that association. - **Sentence position matters.** Putting the structural facts first (three posts, in a line, on the side away from the pavilion) means the model encodes them as the primary schema before it can pattern-match to freestanding. - **Negative instructions are weak.** Saying "NOT four corner posts" is less effective than saying "the only roof support is the pavilion's existing beam" — the latter tells the model what to draw, not what to avoid. - **The slope is the hardest detail.** All three models produced flat roofs in at least one of their outputs. If you want a slope, name the direction explicitly and give a ratio (1:12), not just a description. --- ## What to do if all three apps fail with v2 AND v3 If after both prompts all three apps still produce freestanding 4-post rectangles, the AI image generators on the market right now can't reliably handle this geometry. At that point: 1. **Use ChatGPT or Copilot in image-generation mode and ask it to first describe what it would draw, then generate.** This gives the model a chance to commit to the lean-to geometry in text before it has to commit in pixels. Sometimes describing first helps it self-correct. 2. **Use Adobe Photoshop's Generative Fill** (or Affinity Photo) — manually paint a mask over the metal pergola, then use the inpainting model directly with a short prompt like "redwood craftsman lean-to roof, 3 posts, attached to pavilion, knee braces, 1:12 slope." Inpainting models respect structural context better than text-to-image models because they can see the existing pavilion in the photo. 3. **Use my SVG renderings as the final answer.** They're geometrically accurate, drawn to scale, and show both with and without knee braces. The site at https://pergola.aidalee.com/renderings/ has all three views. --- ## v2 actual results (3 apps tested, 7/10/2026) All three apps produced structurally valid lean-tos in v2, with these specific results: | App | 3 posts in line | 4x4 (not 6x6) | Rafters perpendicular to 4×12 | Rafters attach directly to 4×12 face | Knee braces | Verdict | |---|---|---|---|---|---|---| | **ChatGPT** | ✅ | ❌ Used 6x6 | ❌ Rafters parallel (wrong direction) | ❌ Added a new beam in front of 4×12 | ✅ | **Failed** — wrong rafter direction | | **Gemini** | ✅ | ✅ Correct 4x4 | ✅ Correct | ❌ Added a beam in front of 4×12 (AI can't imagine a joist hanger) | ✅ | **Best of 3** — closest to spec | | **Copilot** | ❌ 4 posts | ❌ Used 6x6 | ❌ Wrong direction | ❌ Rafters landed on existing pavilion posts | ✅ | **Failed** — 4 posts, wrong rafter direction | **Common v2 failure across all 3:** Every model added a NEW horizontal beam between the rafters and the 4×12, instead of having the rafters attach directly to the 4×12 face via joist hangers (LSSJ26). The AI cannot imagine a "beam-to-beam via metal connector" connection — it pattern-matches "lean-to roof" to "rafter sits on a top plate" because that's what house construction looks like. All 3 used 6x6 posts when the spec calls for 4x4. **Why Gemini won:** It was the only one that got 5 of 6 criteria right. The remaining failure (added beam in front of 4×12) is a forgivable AI error since the visual result is similar — both interpretations have rafters meeting a horizontal member at the high side. The 4x4 post sizing and 3-post-on-the-side were the harder structural details, and Gemini got both. **Design insight from the failed renderings:** All 3 models added horizontal side beam boards running perpendicular to the rafters (between the front and back of the new structure). This wasn't in the spec, but it's a real opportunity — those side beams create natural mounting points for ADDITIONAL roller shades on the sides of the structure, not just the front. With shades on the front (east) AND the two sides (north + south), the structure becomes a true 3-sided outdoor room instead of a 2-sided sun-shield. This has been added to the framing plan as a Phase 8.5 option. --- ## File locations - **v1 prompt** (what you tried first): https://pergola.aidalee.com/renderings/PROMPT.md - **v2 prompt** (this file): https://pergola.aidalee.com/renderings/PROMPT-v2.md - **v3 corrections prompt** (for when v2 still fails): included in this file, see above - **Gemini's winning v2 rendering** (added to the site): https://pergola.aidalee.com/renderings/gemini-v2.html