From 1c708c62dc7c7d430796ec0510e421767146bea8 Mon Sep 17 00:00:00 2001
From: parker <parker.g.britt@gmail.com>
Date: Wed, 2 Jul 2025 21:37:46 +0100
Subject: [PATCH] feat: triangle fan triangulation

---
 src/gui/viewport/GLMesh.cpp           | 25 ++++++++++++-------------
 src/gui/viewport/ViewportGLWidget.cpp |  9 +++++----
 2 files changed, 17 insertions(+), 17 deletions(-)

diff --git a/src/gui/viewport/GLMesh.cpp b/src/gui/viewport/GLMesh.cpp
index 59bca08..701f325 100644
--- a/src/gui/viewport/GLMesh.cpp
+++ b/src/gui/viewport/GLMesh.cpp
@@ -15,15 +15,21 @@ void GLMesh::init()
 
     initBuffers();
 
-    vertexPosData = {
-        -0.5f, -0.5f, 0.0f,
-         0.5f, -0.5f, 0.0f,
-         0.0f,  0.5f, 0.0f,
-         0.5f, 0.5f, 0.0f
-    };
+    std::vector<int> foo = {0,1,2,3,4};
+    for(int i=1;i+1<foo.size();++i)
+    {
+        indexData.push_back(foo.at(0));
+        indexData.push_back(foo.at(i));
+        indexData.push_back(foo.at(i+1));
+    }
+    // indexData =
+    // {
+    //     0, 1, 2, 1, 2, 3
+    // };
 
     // store data in the buffer
     glBufferData(GL_ARRAY_BUFFER, vertexPosData.size()*sizeof(GLfloat), vertexPosData.data(), GL_STATIC_DRAW);
+    glBufferData(GL_ELEMENT_ARRAY_BUFFER, indexData.size()*sizeof(GLint), indexData.data(), GL_STATIC_DRAW);
 
 
     // unbind vertex array
@@ -33,12 +39,6 @@ void GLMesh::init()
 void GLMesh::initBuffers()
 {
 
-
-    indexData =
-    {
-        0, 1, 2, 1, 2, 3
-    };
-
     // create buffer of vertices
     glGenBuffers(1, &vertexBuffer);
     // set purpose
@@ -51,7 +51,6 @@ void GLMesh::initBuffers()
 
     glGenBuffers(1, &indexBuffer);
     glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, indexBuffer);
-    glBufferData(GL_ELEMENT_ARRAY_BUFFER, indexData.size()*sizeof(GLint), indexData.data(), GL_STATIC_DRAW);
 
 }
 
diff --git a/src/gui/viewport/ViewportGLWidget.cpp b/src/gui/viewport/ViewportGLWidget.cpp
index f745727..ab1a183 100644
--- a/src/gui/viewport/ViewportGLWidget.cpp
+++ b/src/gui/viewport/ViewportGLWidget.cpp
@@ -149,10 +149,11 @@ std::unique_ptr<GLMesh> ViewportGLWidget::meshFromGeo(std::unique_ptr<enzo::geo:
         
     std::shared_ptr<ga::Attribute> PAttr = geometry->getAttribByName(ga::AttrOwner::POINT, "P");
     ga::AttributeHandleVector3 PAttrHandle = ga::AttributeHandleVector3(PAttr);
-    PAttrHandle.addValue(bt::Vector3(-0.5f, -0.5f, 0.0f));
-    PAttrHandle.addValue(bt::Vector3(0.5f, -0.5f, 0.0f));
-    PAttrHandle.addValue(bt::Vector3(0.0f,  0.5f, 0.0f));
-    PAttrHandle.addValue(bt::Vector3(0.5f, 0.5f, 0.0f));
+    PAttrHandle.addValue(bt::Vector3(1.0f, -1.0f, 0.0f));
+    PAttrHandle.addValue(bt::Vector3(-1.0f, -1.0f, 0.0f));
+    PAttrHandle.addValue(bt::Vector3(-1.0f, 1.0f, 0.0f));
+    PAttrHandle.addValue(bt::Vector3(0.0f, 2.0f, 0.0f));
+    PAttrHandle.addValue(bt::Vector3(1.0f, 1.0f, 0.0f));
 
     mesh->setPosBuffer(PAttrHandle.getData());
     // mesh->setPosBuffer(std::vector<bt::Vector3>{