From 5d4fa4223c4a257969ee2a9bd4e34e32045f9ef9 Mon Sep 17 00:00:00 2001
From: Dirk-Willem van Gulik <dirkx@webweaving.org>
Date: Mon, 7 Feb 2022 21:49:55 +0100
Subject: [PATCH] Allow for the resetting of a graph.

---
 src/elem/XGraph.c | 30 +++++++++++++++++-------------
 src/elem/XGraph.h |  8 ++++++++
 2 files changed, 25 insertions(+), 13 deletions(-)

diff --git a/src/elem/XGraph.c b/src/elem/XGraph.c
index 530c7781d..45dbbc7a9 100644
--- a/src/elem/XGraph.c
+++ b/src/elem/XGraph.c
@@ -92,8 +92,6 @@ gslc_tsElemRef* gslc_ElemXGraphCreate(gslc_tsGui* pGui,int16_t nElemId,int16_t n
   pXData->nMargin         = 5;
 
   pXData->nBufMax         = nBufMax;
-  pXData->nBufCnt         = 0;
-  pXData->nPlotIndStart   = 0;
 
   pXData->colGraph        = colGraph;
   pXData->eStyle          = GSLCX_GRAPH_STYLE_DOT;
@@ -103,17 +101,6 @@ gslc_tsElemRef* gslc_ElemXGraphCreate(gslc_tsGui* pGui,int16_t nElemId,int16_t n
   pXData->nWndHeight = rElem.h - (2*pXData->nMargin);
   pXData->nWndWidth  = rElem.w - (2*pXData->nMargin);
 
-  // Default scale is
-  // - Each data point (buffer row) gets 1 pixel in X direction
-  // - Data value is directly mapped to height in Y direction
-  pXData->nPlotValMin   = 0;
-  pXData->nPlotValMax   = pXData->nWndHeight;
-  pXData->nPlotIndMax   = pXData->nWndWidth;
-
-
-  // Clear the buffer
-  memset(pBuf,0,nBufMax*sizeof(int16_t));
-
 
   // Determine if scrollbar should be enabled
   if (pXData->nPlotIndMax >= pXData->nBufMax) {
@@ -138,6 +125,7 @@ gslc_tsElemRef* gslc_ElemXGraphCreate(gslc_tsGui* pGui,int16_t nElemId,int16_t n
   sElem.colElemFrameGlow  = GSLC_COL_WHITE;
   if (nPage != GSLC_PAGE_NONE) {
     pElemRef = gslc_ElemAdd(pGui,nPage,&sElem,GSLC_ELEMREF_DEFAULT);
+    gslc_ElemXGraphReset(pGui, pElemRef);
     return pElemRef;
 #if (GSLC_FEATURE_COMPOUND)
   } else {
@@ -145,6 +133,7 @@ gslc_tsElemRef* gslc_ElemXGraphCreate(gslc_tsGui* pGui,int16_t nElemId,int16_t n
     pGui->sElemTmp = sElem;
     pGui->sElemRefTmp.pElem = &(pGui->sElemTmp);
     pGui->sElemRefTmp.eElemFlags = GSLC_ELEMREF_DEFAULT | GSLC_ELEMREF_REDRAW_FULL;
+    gslc_ElemXGraphReset(pGui, &(pGui->sElemRefTmp);
     return &(pGui->sElemRefTmp);
 #endif
   }
@@ -239,6 +228,21 @@ void gslc_ElemXGraphAdd(gslc_tsGui* pGui,gslc_tsElemRef* pElemRef,int16_t nVal)
   gslc_ElemSetRedraw(pGui,pElemRef,GSLC_REDRAW_INC);
 }
 
+void gslc_ElemXGraphReset(gslc_tsGui* pGui,gslc_tsElemRef* pElemRef) {
+
+  pXData->nBufCnt         = 0;
+  pXData->nPlotIndStart   = 0;
+
+  // Default scale is
+  // - Each data point (buffer row) gets 1 pixel in X direction
+  // - Data value is directly mapped to height in Y direction
+  pXData->nPlotValMin   = 0;
+  pXData->nPlotValMax   = pXData->nWndHeight;
+  pXData->nPlotIndMax   = pXData->nWndWidth;
+
+  memset(pBuf,0,nBufMax*sizeof(int16_t));
+}
+
 
 bool gslc_ElemXGraphDraw(void* pvGui,void* pvElemRef,gslc_teRedrawType eRedraw)
 {
diff --git a/src/elem/XGraph.h b/src/elem/XGraph.h
index 472c5b264..fd69f4784 100644
--- a/src/elem/XGraph.h
+++ b/src/elem/XGraph.h
@@ -155,6 +155,14 @@ bool gslc_ElemXGraphDraw(void* pvGui,void* pvElemRef,gslc_teRedrawType eRedraw);
 ///
 void gslc_ElemXGraphAdd(gslc_tsGui* pGui,gslc_tsElemRef* pElemRef,int16_t nVal);
 
+/// Reset the graphs values.
+///
+/// \param[in]  pGui:        Pointer to GUI
+/// \param[in]  pElemRef:    Pointer to Element reference
+///
+/// \return none
+///
+void gslc_ElemXGraphReset(gslc_tsGui* pGui,gslc_tsElemRef* pElemRef);
 
 ///
 /// Set the graph scroll position (nScrollPos) as a fraction of