New Grid Primitive, new Coloring visitor and some Scene corrections

src/DrawVisitor.cpp

@@ -21,9 +21,12 @@
 
 #include <glm/gtc/matrix_transform.hpp>
 
+#include "Decorations.h"
 #include "defines.h"
-#include "DrawVisitor.h"
 #include "Scene.h"
+#include "Primitives.h"
+
+#include "DrawVisitor.h"
 
 
 DrawVisitor::DrawVisitor(Node *nodetodraw, glm::mat4 projection, bool force): force_(force)
@@ -115,3 +118,65 @@ void DrawVisitor::visit(Switch &n)
 void DrawVisitor::visit(Primitive &)
 {
 }
+
+
+
+ColorVisitor::ColorVisitor(glm::vec4 color): color_(color)
+{
+
+}
+void ColorVisitor::visit(Node &)
+{
+}
+
+void ColorVisitor::visit(Group &n)
+{
+    // traverse children
+    for (NodeSet::iterator node = n.begin(); node != n.end(); ++node) {
+        (*node)->accept(*this);
+    }
+}
+
+void ColorVisitor::visit(Scene &n)
+{
+    n.root()->accept(*this);
+}
+
+void ColorVisitor::visit(Switch &n)
+{
+    n.activeChild()->accept(*this);
+}
+
+void ColorVisitor::visit(Primitive &p)
+{
+    p.shader()->color = color_;
+}
+
+void ColorVisitor::visit(Frame &d)
+{
+    d.color = color_;
+}
+
+void ColorVisitor::visit(Handles &d)
+{
+    d.color = color_;
+}
+
+void ColorVisitor::visit(Symbol &d)
+{
+    d.color = color_;
+}
+
+void ColorVisitor::visit(Disk &d)
+{
+    d.color = color_;
+}
+
+void ColorVisitor::visit(Character &d)
+{
+    d.color = color_;
+}
+
+
+
+

src/DrawVisitor.h

@@ -1,9 +1,16 @@
 #ifndef DRAWVISITOR_H
 #define DRAWVISITOR_H
 
-#include "GlmToolkit.h"
+#include <vector>
+#include <glm/glm.hpp>
 #include "Visitor.h"
 
+///
+/// \brief The DrawVisitor is typically called on a scene.
+/// It traverses its root and draws only the nodes
+/// listed in the constructor. The nodes listed must already
+/// be in the hierarchy of the scene
+///
 class DrawVisitor : public Visitor
 {
     glm::mat4 modelview_;
@@ -26,4 +33,31 @@ public:
     void visit(Switch& n) override;
 };
 
+
+///
+/// \brief The ColorVisitor changes the colors of
+/// all nodes that can draw (e.g. primitive, decorations)
+/// to the given color
+///
+class ColorVisitor : public Visitor
+{
+    glm::vec4 color_;
+
+public:
+    ColorVisitor(glm::vec4 color);
+
+    void visit(Scene& n) override;
+    void visit(Node& n) override;
+    void visit(Group& n) override;
+    void visit(Switch& n) override;
+
+    void visit(Primitive& ) override;
+    void visit(Frame& ) override;
+    void visit(Handles& ) override;
+    void visit(Symbol& ) override;
+    void visit(Disk& ) override;
+    void visit(Character& ) override;
+};
+
+
 #endif // DRAWVISITOR_H

src/Primitives.cpp

@@ -192,7 +192,7 @@ void Points::accept(Visitor& v)
 
 
 
-HLine::HLine(float linewidth): Primitive(new Shader), width(linewidth)
+HLine::HLine(float linewidth, Shader *s): Primitive(s), width(linewidth)
 {
     //                      1       3
     //                      +-------+        ^
@@ -216,9 +216,6 @@ HLine::HLine(float linewidth): Primitive(new Shader), width(linewidth)
 
     // default scale
     scale_.y = width;
-
-    //default color
-    color = glm::vec4( 1.f, 1.f, 1.f, 1.f);
 }
 
 HLine::~HLine()
@@ -271,13 +268,10 @@ void HLine::draw(glm::mat4 modelview, glm::mat4 projection)
     scale_.y = (float) width / vec.y;
     update(0);
 
-    // change color
-    shader_->color = color;
-
     Primitive::draw(modelview, projection);
 }
 
-VLine::VLine(float linewidth): Primitive(new Shader), width(linewidth)
+VLine::VLine(float linewidth, Shader *s): Primitive(s), width(linewidth)
 {
     points_ = std::vector<glm::vec3> { glm::vec3( 0.f, -1.f, 0.f ),
             glm::vec3( 0.001f, -0.999f, 0.f ),
@@ -293,9 +287,6 @@ VLine::VLine(float linewidth): Primitive(new Shader), width(linewidth)
 
     // default scale
     scale_.x = width;
-
-    // default color
-    color = glm::vec4( 1.f, 1.f, 1.f, 1.f);
 }
 
 VLine::~VLine()
@@ -348,45 +339,53 @@ void VLine::draw(glm::mat4 modelview, glm::mat4 projection)
     scale_.x = width / vec.x;
     update(0);
 
-    // change color
-    shader_->color = color;
-
     Primitive::draw(modelview, projection);
 }
 
 LineSquare::LineSquare(float linewidth) : Group()
 {
-    top_    = new HLine(linewidth);
+    shader__ = new Shader;
+
+    top_    = new HLine(linewidth, shader__);
     top_->translation_ = glm::vec3(0.f, 1.f, 0.f);
     attach(top_);
-    bottom_ = new HLine(linewidth);
+    bottom_ = new HLine(linewidth, shader__);
     bottom_->translation_ = glm::vec3(0.f, -1.f, 0.f);
     attach(bottom_);
-    left_   = new VLine(linewidth);
+    left_   = new VLine(linewidth, shader__);
     left_->translation_ = glm::vec3(-1.f, 0.f, 0.f);
     attach(left_);
-    right_  = new VLine(linewidth);
+    right_  = new VLine(linewidth, shader__);
     right_->translation_ = glm::vec3(1.f, 0.f, 0.f);
     attach(right_);
 }
 
-
 LineSquare::LineSquare(const LineSquare &square)
 {
-    top_    = new HLine(square.top_->width);
+    shader__ = new Shader;
+    shader__->color = square.color();
+
+    top_    = new HLine(square.top_->width, shader__);
     top_->translation_ = glm::vec3(0.f, 1.f, 0.f);
     attach(top_);
-    bottom_ = new HLine(square.bottom_->width);
+    bottom_ = new HLine(square.bottom_->width, shader__);
     bottom_->translation_ = glm::vec3(0.f, -1.f, 0.f);
     attach(bottom_);
-    left_   = new VLine(square.left_->width);
+    left_   = new VLine(square.left_->width, shader__);
     left_->translation_ = glm::vec3(-1.f, 0.f, 0.f);
     attach(left_);
-    right_  = new VLine(square.right_->width);
+    right_  = new VLine(square.right_->width, shader__);
     right_->translation_ = glm::vec3(1.f, 0.f, 0.f);
     attach(right_);
+}
 
-    setColor(square.color());
+LineSquare::~LineSquare()
+{
+    top_->replaceShader(nullptr);
+    bottom_->replaceShader(nullptr);
+    left_->replaceShader(nullptr);
+    right_->replaceShader(nullptr);
+    delete shader__;
 }
 
 void LineSquare::setLineWidth(float v)
@@ -397,12 +396,74 @@ void LineSquare::setLineWidth(float v)
     right_->width = v;
 }
 
-void LineSquare::setColor(glm::vec4 c)
+LineGrid::LineGrid(size_t N, float step, float linewidth)
 {
-    top_->color = c;
-    bottom_->color = c;
-    left_->color = c;
-    right_->color = c;
+    shader__ = new Shader;
+    N = MAX(1, N);
+
+    for (size_t n = 0; n < N ; ++n) {
+        VLine *l = new VLine(linewidth, shader__);
+        l->translation_.x = (float)n * step;
+        l->scale_.y = (float)N * step;
+        attach(l);
+    }
+    for (size_t n = 1; n < N ; ++n) {
+        VLine *l = new VLine(linewidth, shader__);
+        l->translation_.x = (float)n * -step;
+        l->scale_.y = (float)N * step;
+        attach(l);
+    }
+    for (size_t n = 0; n < N ; ++n) {
+        HLine *l = new HLine(linewidth, shader__);
+        l->translation_.y = (float)n * step;
+        l->scale_.x = (float)N * step;
+        attach(l);
+    }
+    for (size_t n = 1; n < N ; ++n) {
+        HLine *l = new HLine(linewidth, shader__);
+        l->translation_.y = (float)n * -step;
+        l->scale_.x = (float)N * step;
+        attach(l);
+    }
+}
+
+LineGrid::~LineGrid()
+{
+    // prevent nodes from deleting the shader
+    for (NodeSet::iterator node = begin(); node != end(); ++node) {
+        Primitive *p = dynamic_cast<Primitive *>(*node);
+        if (p)
+            p->replaceShader(nullptr);
+    }
+    delete shader__;
+}
+
+void LineGrid::setLineWidth(float v)
+{
+    for (NodeSet::iterator node = begin(); node != end(); ++node) {
+        VLine *vl = dynamic_cast<VLine *>(*node);
+        if (vl) {
+            vl->width = v;
+            continue;
+        }
+        HLine *hl = dynamic_cast<HLine *>(*node);
+        if (hl)
+            hl->width = v;
+    }
+}
+
+float LineGrid::lineWidth() const
+{
+    Node *n = front();
+    if (n) {
+        VLine *vl = dynamic_cast<VLine *>(n);
+        if (vl)
+            return vl->width;
+        HLine *hl = dynamic_cast<HLine *>(n);
+        if (hl)
+            return hl->width;
+    }
+    return 0.f;
 }
 
 LineStrip::LineStrip(const std::vector<glm::vec2> &path, float linewidth) : Primitive(new Shader),

src/Primitives.h

@@ -108,13 +108,12 @@ class HLine : public Primitive {
 
 public:
 
-    HLine(float width = 1.f);
+    HLine(float width = 1.f, Shader *s = new Shader);
     virtual ~HLine();
 
     void init () override;
     void draw(glm::mat4 modelview, glm::mat4 projection) override;
 
-    glm::vec4 color;
     float width;
 };
 
@@ -122,13 +121,12 @@ class VLine : public Primitive {
 
 public:
 
-    VLine(float width = 1.f);
+    VLine(float width = 1.f, Shader *s = new Shader);
     virtual ~VLine();
 
     void init () override;
     void draw(glm::mat4 modelview, glm::mat4 projection) override;
 
-    glm::vec4 color;
     float width;
 };
 
@@ -137,18 +135,38 @@ public:
  */
 class LineSquare : public Group {
 
+    Shader *shader__;
     HLine *top_, *bottom_;
     VLine *left_, *right_;
 
 public:
     LineSquare(float linewidth = 1.f);
     LineSquare(const LineSquare &square);
+    virtual ~LineSquare();
 
     void setLineWidth(float v);
     inline float lineWidth() const { return top_->width; }
 
-    void setColor(glm::vec4 c);
-    inline glm::vec4 color() const { return top_->color; }
+    inline void setColor(glm::vec4 c) { shader__->color = c; }
+    inline glm::vec4 color() const { return shader__->color; }
+};
+
+/**
+ * @brief The Grid class is a group of NxN vertical and horizontal lines
+ */
+class LineGrid : public Group {
+
+    Shader *shader__;
+
+public:
+    LineGrid(size_t N, float step, float linewidth = 1.f);
+    ~LineGrid();
+
+    void setLineWidth(float v);
+    float lineWidth() const;
+
+    inline void setColor(glm::vec4 c) { shader__->color = c; }
+    inline glm::vec4 color() const { return shader__->color; }
 };
 
 /**

src/Scene.cpp

@@ -230,10 +230,10 @@ void Primitive::replaceShader( Shader *newshader )
             color = shader_->color;
             delete shader_;
         }
-        shader_ = newshader;
         shader_->iTransform = iTransform;
         shader_->color = color;
     }
+    shader_ = newshader;
 }
 
 //
@@ -268,7 +268,6 @@ void Group::attach(Node *child)
     }
 }
 
-
 void Group::sort()
 {
     // reorder list of nodes
@@ -338,17 +337,17 @@ NodeSet::iterator Group::end()
 }
 
 
-Node *Group::front()
+Node *Group::front() const
 {
     if (!children_.empty())
-        return *children_.rbegin();
+        return *children_.crbegin();
     return nullptr;
 }
 
-Node *Group::back()
+Node *Group::back() const
 {
     if (!children_.empty())
-        return *children_.begin();
+        return *children_.cbegin();
     return nullptr;
 }
 

src/Scene.h

@@ -178,8 +178,8 @@ public:
     void sort();
     NodeSet::iterator begin();
     NodeSet::iterator end();
-    Node *front();
-    Node *back();
+    Node *front() const;
+    Node *back() const;
 
 protected:
     NodeSet children_;