Performance Optimization

Draw points can accept multiple colors.

Draw points now uses vbos.

Allowed the user to set the usage hint for the VBO.

When changing data in a vbo, the data will be orphaned if the mode is not Fixed.

include/JGL/JGL.h

@@ -47,6 +47,8 @@ namespace JGL::ShapeCache {
     // Facing straight out.
     inline VRamList* j2d_default_normal_data = nullptr;
     inline VRamList* square_origin_topleft_vertex_data = nullptr;
+    inline VRamList* draw_points_positions = nullptr;
+    inline VRamList* draw_points_colors = nullptr;
     void Init();
 }
 
@@ -96,7 +98,14 @@ namespace JGL::J2D {
 
     /// Plots a series of pixel-points on the screen, in a batch.
     /// @note This is more performant for multiple points than plotting them individually.
-    /// @param color A 3-or-4 channel color value. @see class Color3, class Color4
+    /// @param colors A set of 4 channel color values. @see class Color4.
+    /// @param points A set of x,y points to render.
+    /// @param radius The size of the point to plot. By default, a single pixel.
+    void DrawPoints(const Color4* color, const Vector2* points, int point_count, float radius = 1.f);
+
+    /// Plots a series of pixel-points on the screen, in a batch.
+    /// @note This is more performant for multiple points than plotting them individually.
+    /// @param color  A 3-or-4 channel color value. @see class Color3, class Color4
     /// @param points A set of x,y points to render.
     /// @param radius The size of the point to plot. By default, a single pixel.
     void DrawPoints(const Color4& color, const Vector2* points, int point_count, float radius = 1.f);

include/JGL/types/VRamList.h

@@ -5,18 +5,28 @@
 #include <J3ML/LinearAlgebra/Vector2i.hpp>
 #include <J3ML/LinearAlgebra/Vector3.hpp>
 #include <J3ML/LinearAlgebra/Vector4.hpp>
+#include <Color4.hpp>
 
 namespace JGL {
     class VRamList;
+    /// A hint for OpenGL on how the VBO is to be used.
+    enum VRamUsageHint : GLenum {
+        // Never updated after creation.
+        Fixed = GL_STATIC_DRAW,
+        // Modified occasionally.
+        Dynamic = GL_DYNAMIC_DRAW,
+        // Constantly modified and used one or a few times.
+        Stream = GL_STREAM_DRAW
+    };
 }
 
 /// A wrapped for "Vertex Buffer Object" In OpenGL, Store things in VRam.
 class JGL::VRamList {
 private:
+    VRamUsageHint usage_hint = Fixed;
     GLuint list_handle = 0;
     long num_elements = 0;
     bool element_array_buffer = false;
-    /// "Spin Locking" fix for multi-threading.
     bool spin_lock = false;
     void load(const GLfloat* data, const long& size);
     void load(const GLuint* data, const long& size);
@@ -24,11 +34,12 @@ private:
     void UpdateData(void* data, const long& offset, const long& count);
     void Erase();
 public:
-    VRamList(const GLuint* data, const long& count);
-    VRamList(const GLfloat* data, const long& count);
-    VRamList(const Vector2* data, const long& count);
-    VRamList(const Vector3* data, const long& count);
-    VRamList(const Vector4* data, const long& count);
+    VRamList(const GLuint* data, const long& count, VRamUsageHint hint = Fixed);
+    VRamList(const GLfloat* data, const long& count, VRamUsageHint hint = Fixed);
+    VRamList(const Vector2* data, const long& count, VRamUsageHint hint = Fixed);
+    VRamList(const Vector3* data, const long& count, VRamUsageHint hint = Fixed);
+    VRamList(const Vector4* data, const long& count, VRamUsageHint hint = Fixed);
+    VRamList(const Color4* data, const long& count, VRamUsageHint hint = Fixed);
 
     ~VRamList();
     /** Copying around the VBO data to a new VBO like this is slow.
@@ -51,6 +62,7 @@ public:
     void SetData(const Vector2* data, const long& count);
     void SetData(const Vector3* data, const long& count);
     void SetData(const Vector4* data, const long& count);
+    void SetData(const Color4* data, const long& count);
 
     void SetData(const GLuint* data, const long& count);
     void SetData(const Vector2i* data, const long& count);
@@ -62,7 +74,7 @@ public:
      void UpdateData(const Vector2* data, const long& offset, const long& count);
      void UpdateData(const Vector3* data, const long& offset, const long& count);
      void UpdateData(const Vector4* data, const long& offset, const long& count);
-
+     void UpdateData(const Color4* data, const long& offset, const long& count);
      void UpdateData(const GLuint* data, const long& offset, const long& count);
      void UpdateData(const Vector2i* data, const long& offset, const long& count);
 };

src/ShapeCache.cpp

@@ -54,4 +54,14 @@ void JGL::ShapeCache::Init() {
         std::array<GLfloat, 3> normal {0, 0, 1};
         j2d_default_normal_data = new VRamList(normal.data(), normal.size());
     }
+
+    if (!draw_points_colors) {
+        std::array<Color4, 1> color = { Colors::Transparent };
+        draw_points_colors = new VRamList(color.data(), color.size(), Stream);
+    }
+
+    if (!draw_points_positions) {
+        std::array<Vector2, 1> position =  { Vector2::Zero };
+        draw_points_positions = new VRamList(position.data(), position.size(), Stream);
+    }
 }

src/renderer/OpenGL/J2D.cpp

@@ -1038,11 +1038,32 @@ void J2D::OutlineChamferRect(const Color4& color, const Vector2& pos, const Vect
     glColor4fv(default_state.draw_color);
 }
 
-void J2D::DrawPoints(const Color4& color, const Vector2* points, int num_points, float radius) {
+void J2D::DrawPoints(const Color4* colors, const Vector2* points, int point_count, float radius) {
+    ShapeCache::draw_points_colors->SetData(colors, point_count);
+    ShapeCache::draw_points_positions->SetData(points, point_count);
+
+    glPointSize(radius);
+    glEnableClientState(GL_COLOR_ARRAY);
+    glBindBuffer(GL_ARRAY_BUFFER, ShapeCache::draw_points_colors->GetHandle());
+    glColorPointer(4, GL_UNSIGNED_BYTE, sizeof(Color4), nullptr);
+
+    glBindBuffer(GL_ARRAY_BUFFER, ShapeCache::draw_points_positions->GetHandle());
+    glVertexPointer(2, GL_FLOAT, sizeof(Vector2), nullptr);
+    glDrawArrays(GL_POINTS, 0, point_count);
+    glDisableClientState(GL_COLOR_ARRAY);
+    glBindBuffer(GL_ARRAY_BUFFER, 0);
+    glColor4fv(default_state.draw_color);
+}
+
+void J2D::DrawPoints(const Color4& color, const Vector2* points, int point_count, float radius) {
+    ShapeCache::draw_points_positions->SetData(points, point_count);
     glPointSize(radius);
     glColor4ubv(color.ptr());
-    glVertexPointer(2, GL_FLOAT, sizeof(Vector2), points);
-    glDrawArrays(GL_POINTS, 0, num_points);
+    glBindBuffer(GL_ARRAY_BUFFER, ShapeCache::draw_points_positions->GetHandle());
+    glVertexPointer(2, GL_FLOAT, sizeof(Vector2), nullptr);
+    glDrawArrays(GL_POINTS, 0, point_count);
+    glDisableClientState(GL_COLOR_ARRAY);
+    glBindBuffer(GL_ARRAY_BUFFER, 0);
     glColor4fv(default_state.draw_color);
 }
 

src/types/VRamList.cpp

@@ -2,15 +2,16 @@
 #include <JGL/logger/logger.h>
 #include <cstring>
 
+// TODO combine the two load functions.
+
 void JGL::VRamList::load(const GLfloat* data, const long& size) {
-    while (spin_lock) {}
     spin_lock = true;
 
     GLint current_array_buffer = 0;
     glGetIntegerv(GL_ARRAY_BUFFER_BINDING, &current_array_buffer);
     glGenBuffers(1, &list_handle);
     glBindBuffer(GL_ARRAY_BUFFER, list_handle);
-    glBufferData(GL_ARRAY_BUFFER, size, data, GL_STATIC_DRAW);
+    glBufferData(GL_ARRAY_BUFFER, size, data, usage_hint);
     glBindBuffer(GL_ARRAY_BUFFER, current_array_buffer);
     element_array_buffer = false;
     num_elements = size / sizeof(GLfloat);
@@ -18,15 +19,15 @@ void JGL::VRamList::load(const GLfloat* data, const long& size) {
     spin_lock = false;
 }
 
+
 void JGL::VRamList::load(const GLuint* data, const long& size) {
-    while (spin_lock) {}
     spin_lock = true;
 
     GLint current_element_array_buffer = 0;
     glGetIntegerv(GL_ELEMENT_ARRAY_BUFFER_BINDING, &current_element_array_buffer);
     glGenBuffers(1, &list_handle);
     glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, list_handle);
-    glBufferData(GL_ELEMENT_ARRAY_BUFFER, size, data, GL_STATIC_DRAW);
+    glBufferData(GL_ELEMENT_ARRAY_BUFFER, size, data, usage_hint);
     glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, current_element_array_buffer);
     element_array_buffer = true;
     num_elements = size / sizeof(GLuint);
@@ -77,6 +78,7 @@ size_t JGL::VRamList::GetDataSize() const {
 }
 
 void JGL::VRamList::SetData(void* data, const long& length) {
+
     while (spin_lock) {}
     spin_lock = true;
 
@@ -100,14 +102,11 @@ void JGL::VRamList::SetData(void* data, const long& length) {
     glGetIntegerv(buffer_binding, &current_buffer);
     glBindBuffer(buffer_type, list_handle);
 
-    void* vram = glMapBuffer(buffer_type, GL_WRITE_ONLY);
-    if (!vram)
-        JGL::Logger::Fatal("Mapping in a VBO that doesn't exist?");
+    size_t element_size = element_array_buffer ? sizeof(GLuint) : sizeof(GLfloat);
 
-    memcpy(vram, data, (element_array_buffer ? sizeof(GLuint) : sizeof(GLfloat)) * length);
-    
-    if (!glUnmapBuffer(buffer_type))
-        JGL::Logger::Fatal("We couldn't unmap the buffer?");
+    if (usage_hint != Fixed)
+        glBufferData(GL_ARRAY_BUFFER, length * element_size, nullptr, usage_hint);
+    glBufferSubData(buffer_type, 0, length * element_size, data);
 
     glBindBuffer(buffer_type, current_buffer);
 
@@ -119,7 +118,6 @@ void JGL::VRamList::UpdateData(void* data, const long& offset, const long& lengt
     spin_lock = true;
 
     if (offset + length > num_elements) {
-        JGL::Logger::Warning("Using UpdateData to out-of-bounds write the VRamList? I'll resize it for you, But this is slow.");
         unsigned long oob_delta = (offset + length) - num_elements;
 
         if (element_array_buffer) {
@@ -149,15 +147,11 @@ void JGL::VRamList::UpdateData(void* data, const long& offset, const long& lengt
     glGetIntegerv(buffer_binding, &current_buffer);
     glBindBuffer(buffer_type, list_handle);
 
-    void* vram = glMapBuffer(buffer_type, GL_WRITE_ONLY);
-    if (!vram)
-        JGL::Logger::Fatal("Mapping in a VBO that doesn't exist?");
-
     size_t element_size = element_array_buffer ? sizeof(GLuint) : sizeof(GLfloat);
-    memcpy(reinterpret_cast<void*>(reinterpret_cast<uintptr_t>(vram) + (offset * element_size)), data, length * element_size);
 
-    if (!glUnmapBuffer(buffer_type))
-        JGL::Logger::Fatal("We couldn't unmap the buffer?");
+    if (usage_hint != Fixed)
+        glBufferData(GL_ARRAY_BUFFER, length * element_size, nullptr, usage_hint);
+    glBufferSubData(buffer_type, offset * element_size, length * element_size, data);
 
     glBindBuffer(buffer_type, current_buffer);
 
@@ -217,26 +211,35 @@ std::vector<GLuint> JGL::VRamList::GetDataUI() const {
     return data;
 }
 
-JGL::VRamList::VRamList(const GLfloat* data, const long& length) {
+JGL::VRamList::VRamList(const GLfloat* data, const long& length, VRamUsageHint hint) {
+    usage_hint = hint;
     load(data, (long) sizeof(GLfloat) * length);
 }
 
-JGL::VRamList::VRamList(const GLuint* data, const long& length) {
+JGL::VRamList::VRamList(const GLuint* data, const long& length, VRamUsageHint hint) {
+    usage_hint = hint;
     load(data, (long) sizeof(GLuint) * length);
 }
 
-JGL::VRamList::VRamList(const Vector2* data, const long& length) {
+JGL::VRamList::VRamList(const Vector2* data, const long& length, VRamUsageHint hint) {
+    usage_hint = hint;
     load(reinterpret_cast<const GLfloat*>(data), (long) sizeof(Vector2) * length);
 }
 
-JGL::VRamList::VRamList(const Vector3* data, const long& length) {
+JGL::VRamList::VRamList(const Vector3* data, const long& length, VRamUsageHint hint) {
+    usage_hint = hint;
     load(reinterpret_cast<const GLfloat*>(data), (long) sizeof(Vector3) * length);
 }
 
-JGL::VRamList::VRamList(const Vector4* data, const long& length) {
+JGL::VRamList::VRamList(const Vector4* data, const long& length, VRamUsageHint hint) {
+    usage_hint = hint;
     load(reinterpret_cast<const GLfloat*>(data), (long) sizeof(Vector4) * length);
 }
 
+JGL::VRamList::VRamList(const Color4* data, const long& count, VRamUsageHint hint) {
+    usage_hint = hint;
+    load(reinterpret_cast<const GLfloat *>(data), (long) sizeof(GLuint) * count);
+}
 void JGL::VRamList::SetData(const GLfloat* data, const long& length) {
     SetData((void*) data, length);
 }
@@ -261,6 +264,10 @@ void JGL::VRamList::SetData(const Vector2i* data, const long& length) {
     SetData((void*) data, length * 2);
 }
 
+void JGL::VRamList::SetData(const Color4* data, const long& count) {
+    SetData((void*) data, count);
+}
+
 void JGL::VRamList::UpdateData(const GLfloat* data, const long& offset, const long& length) {
     UpdateData((void*) data, offset, length);
 }
@@ -285,6 +292,10 @@ void JGL::VRamList::UpdateData(const Vector2i* data, const long& offset, const l
     UpdateData((void*) data, offset, length * 2);
 }
 
+void JGL::VRamList::UpdateData(const Color4* data, const long &offset, const long &count) {
+    UpdateData((void*) data, offset, count);
+}
+
 JGL::VRamList::~VRamList() {
     Erase();
 }