GRAPH: Random pixels at borders

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    • GRAPH: Random pixels at borders

      in a GRAPH widget I want to display a scale in the border area.
      I have added 10 pixels border on the right and on the bottom side.
      In these border areas frequently appear random pixels. Did I miss something in my initialization?


      Source Code

      1. hGraph = WM_GetDialogItem(pMsg->hWin, ID_GRAPH);
      2. GRAPH_SetAutoScrollbar(hGraph, GUI_COORD_X, 0); /*disable GRAPH hor. scrollbar*/
      3. GRAPH_SetAutoScrollbar(hGraph, GUI_COORD_Y, 0); /*disable GRAPH vert. scrollbar*/
      4. GRAPH_SetColor(hGraph, GUI_GRAY, GRAPH_CI_GRID);
      5. GRAPH_SetColor(hGraph, GUI_GRAY, GRAPH_CI_FRAME);
      6. GRAPH_SetColor(hGraph, GUI_BLACK, GRAPH_CI_BORDER);
      7. GRAPH_SetColor(hGraph, GUI_BLACK, GRAPH_CI_BK);
      8. GRAPH_SetGridFixedX(hGraph, 1);
      9. GRAPH_SetGridDistX(hGraph, (FFTWidthMaCon) / 10);
      10. GRAPH_SetGridDistY(hGraph, FFTVerSizeMaCon / 8);
      11. GRAPH_SetGridVis(hGraph, 1);
      12. GRAPH_SetLineStyleH(hGraph, GUI_LS_DOT);
      13. GRAPH_SetLineStyleV(hGraph, GUI_LS_DOT);
      14. GRAPH_SetBorder(hGraph, 0, 0, 10, 10);
      15. hScaleH = GRAPH_SCALE_Create(FFTVerSizeMaCon, GUI_TA_CENTER, GRAPH_SCALE_CF_HORIZONTAL, FFTWidthMaCon / 10); /*create hor. scale*/
      16. GRAPH_SCALE_SetTextColor(hScaleH, GUI_WHITE);
      17. GRAPH_SCALE_SetFont(hScaleH, GUI_FONT_10_1);
      18. GRAPH_SCALE_SetNumDecs(hScaleH, 0); /*no digits after decimal point*/
      19. GRAPH_SCALE_SetFactor(hScaleH, 200.0 / (float)(FFTWidthMaCon - 1));
      20. GRAPH_AttachScale(hGraph, hScaleH);
      Display All
    • Hello Jan,

      Which device are you using and which emWin driver?

      It looks a bit like as if the data where not entirely written into the framebuffer but reside in the CPU cache.

      For example, on STM32 devices devices we call SCB_CleanInvalidateDCache() before any DMA2D operation to ensure the data is properly written into the RAM.

      Best regards,
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