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I'm mapping able points to archaeological research. Using QGIS, I need to create a regular grid of sample points, give them a value, specifying spacing and rotation. Better if it results inside a polygon.

I'd find some plugins and core actions in QGIS but none of them fully achieved my goal. ArcMap has Create Fishnet that is quite close what I'm looking for but it's not possible to create fields with incremental value allowing points to have ID (A1, A2... B1, B2...). After create it, as Create Fishnet output results in line or polygon feature. I have to use Intersect and Merge to create a point grid.

I'm a beginner in programming. Maybe I can have some tips how to start focused on that.

I can describe a process:

  1. Choose origin grid reference - Maybe a single point feature on a polygon corner or coordinate
  2. Input an angle value - Measured in one side of the polygon or opposite corner
  3. Space between point in x-axis
  4. Space between point in y-axis
  5. Number of columns x-axis
  6. Number of lines y-axis
  7. Create field X_AXIS: Input incremental string value by row(A,B,C...Z,AA,BB,CC...)
  8. Create field Y_AXIS: Input incremental integer value column (1,2,3...)
  9. Create field POINT_ID: Concatenate X_AXIS and Y_AXIS
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    A small idea: fast way from polygon grid to points is to take centroids. – user30184 Apr 30 '15 at 18:47
  • About Create Fishnet, I'm intersecting lines and generate points. If use centroids I won't have a point in grid origin. – Fausto Isolan Apr 30 '15 at 19:09
  • But you are clever enough for calculating the shifts but that is not a big deal really. – user30184 Apr 30 '15 at 19:46
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    I agree with @user30184 - you can use centroid if you simply offset your grid to make the centroid appear where your grid corners/desired points should be (ie, origin is -1/2 value of xy cell size). With Fishnet, it can even create those points for you as part of the process. I'm not aware of any basic grid tool that has much in the way of label functionality, or at least allows for customizing labels and their order/grid path. That's usually a separate attribute process or part of a specialized map book extension. Related: gis.stackexchange.com/questions/138930 – Chris W May 1 '15 at 0:44
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You can get rather close with OpenJUMP

Select the layer that covers your research area.

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Create a grid with desired spacing as line grid, polygon grid, or point grid.

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Grid features will have one attribute that is a combination of X and Y coordinates. If you want a rotated grid make the grid layer editable, select all features and use the Rotate Selected Item tool.

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Result is not perfect when it comes to labels. Perhaps it is possible to create a new attribute that is better for labeling by using some attribute calculator tool.

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