| 48 | 6. About the position of watermark: there are two types of position in watermark: XY position and tile position. Tile position means the watermark will repeat itself in the map image (it has nothing to do with tile service). |
| 49 | I) The offset for tile position is the offset of watermark within tile (repeat unit), not map image. |
| 50 | II) The alignment base of offset is different depending on the alignment way. For horizontal alignment: |
| 51 | i) If the alignment is left, then the offset means the distance between left edge of watermark and that of map image / tile. |
| 52 | ii) If the alignment is center, then the offset means the distance between center of X-axis of watermark and that of map image / tile. |
| 53 | iii) If the alignment is right, then the offset means the distance between right edge of watermark and that of map image / tile. |
| 54 | For vertical alignment: |
| 55 | i) If the alignment is top, then the offset means the distance between top edge of watermark and that of map image / tile. |
| 56 | ii) If the alignment is center, then the offset means the distance between center of Y-axis of watermark and that of map image / tile. |
| 57 | iii) If the alignment is bottom, then the offset means the distance between bottom edge of watermark and that of map image / tile. |
| 59 | Here are several examples: |
| 60 | a) XY position: X-Offset: 10 pixels from right, Y-Offset: 20 pixels from bottom. Watermark is a 40 * 30 pixel image. Map image size 400*300 pixels. Then the position of watermark is: |
| 61 | The left edge of watermark is 400 - 10 - 40 = 350 pixels (ImageWidth - XOffset - WatermarkWidth) from left edge of map image. |
| 62 | The top edge of watermark is 300 - 20 - 30 = 250 pixels (ImageHeight - YOffset - WatermarkHeight) from top edge of map image. |
| 63 | b) Tile position: X-Offset: 10 pixels from right, Y-Offset: 20 pixels from bottom. Tile width: 210 pixels, tile height: 170px. Watermark is a 40 * 30 pixel image. Map image size 400*300 pixels. There will be four watermarks in map: |
| 64 | i) Left: 210 - 10 - 40 = 160, Top: 170 - 20 - 30 = 120 |
| 65 | ii) Left: 2*210 - 10 - 40 = 370, Top: 170 - 20 - 30 = 120 (part of watermark is not visible for out of map image bound). |
| 66 | iii) Left: 2*210 - 10 - 40 = 370, Top: 170*2 - 20 - 30 = 290 (part of watermark is visible for out of map image bound). |
| 67 | iv) Left: 210 - 10 - 40 = 160, Top: 170*2 - 20 - 30 = 290 (part of watermark is visible for out of map image bound). |
| 68 | The unit of watermark position is the unit of "paper length", not the "actual length in map". So it will not align with the existing unit list in layer definition. |