mesh and vertex buffer

src/dlangui/graphics/glsupport.d

@@ -1023,8 +1023,9 @@ alias VBO = GLObject!(GLObjectTypes.Buffer, GL_ARRAY_BUFFER);
 alias Tex2D = GLObject!(GLObjectTypes.Texture, GL_TEXTURE_2D);
 alias FBO = GLObject!(GLObjectTypes.Framebuffer, GL_FRAMEBUFFER);
 
-class VertexBuffer : VertexBufferBase {
+class GLVertexBuffer : VertexBuffer {
     protected VertexFormat _format;
+    protected IndexFragment[] _indexFragments;
     protected GLuint _vertexBuffer;
     protected GLuint _indexBuffer;
     protected GLuint _vao;
@@ -1066,20 +1067,10 @@ class VertexBuffer : VertexBufferBase {
         }
     }
 
-    void updateVertexFormat() {
-        // TODO: use vertex attributes from format and shaders
-        glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, _format.vertexSize, cast(char*)(0));
-        glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, _format.vertexSize, cast(char*)(float.sizeof*3));
-        glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, _format.vertexSize, cast(char*)(float.sizeof*6));
-
-        glEnableVertexAttribArray(0);
-        glEnableVertexAttribArray(1);
-        glEnableVertexAttribArray(2);
-    }
-
     /// set or change data
     override void setData(Mesh mesh) {
         _format = mesh.vertexFormat;
+        _indexFragments = mesh.indexFragments;
         // vertex buffer
         checkgl!glBindBuffer(GL_ARRAY_BUFFER, _vertexBuffer);
         checkgl!glBufferData(GL_ARRAY_BUFFER, _format.vertexSize * mesh.vertexCount, mesh.vertexData.ptr, GL_STATIC_DRAW);
@@ -1091,11 +1082,38 @@ class VertexBuffer : VertexBufferBase {
         checkgl!glBindVertexArray(_vao);
         // specify vertex buffer
         checkgl!glBindBuffer(GL_ARRAY_BUFFER, _vertexBuffer);
-        // set vertex buffer format
-        updateVertexFormat();
         // specify index buffer
         checkgl!glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, _indexBuffer);
 
         unbind();
     }
+
+    /// draw mesh using specified effect
+    override void draw(GraphicsEffect effect) {
+        bind();
+        prepareDrawing(effect);
+        foreach (fragment; _indexFragments) {
+            glDrawRangeElements(primitiveTypeToGL(fragment.type), 
+                                fragment.start, fragment.end, 
+                                fragment.end - fragment.start, 
+                                GL_UNSIGNED_SHORT, null);
+        }
+        unbind();
+    }
+}
+
+GLenum primitiveTypeToGL(PrimitiveType type) {
+    switch(type) with (PrimitiveType) {
+        case triangles:
+            return GL_TRIANGLES;
+        case triangleStripes:
+            return GL_TRIANGLE_STRIP;
+        case lines:
+            return GL_LINES;
+        case lineStripes:
+            return GL_LINE_STRIP;
+        case points:
+        default:
+            return GL_POINTS;
+    }
 }

src/dlangui/graphics/scene/mesh.d

@@ -3,6 +3,7 @@ module dlangui.graphics.scene.mesh;
 import dlangui.graphics.scene.material;
 import dlangui.core.math3d;
 
+/// vertex element type
 enum VertexElementType : ubyte {
     POSITION = 1,
     NORMAL,
@@ -17,8 +18,17 @@ enum VertexElementType : ubyte {
     TEXCOORD7,
 }
 
+/// Graphics primitive type
+enum PrimitiveType : int {
+    triangles,
+    triangleStripes,
+    lines,
+    lineStripes,
+    points,
+}
+
 /// Vertex buffer object base class
-class VertexBufferBase {
+class VertexBuffer {
     /// bind into current context
     void bind() {}
     /// unbind from current context
@@ -27,6 +37,8 @@ class VertexBufferBase {
     void setData(Mesh mesh) { }
     /// update vertex element locations for effect/shader program
     void prepareDrawing(GraphicsEffect effect) { }
+    /// draw mesh using specified effect
+    void draw(GraphicsEffect effect) { }
 }
 
 /// location for element is not found
@@ -61,7 +73,7 @@ struct VertexElement {
                 case COLOR:
                     size = 4;
                     break;
-                default:
+                default: // tx coords
                     size = 2;
                     break;
             }
@@ -126,12 +138,24 @@ struct VertexFormat {
     }
 }
 
+struct IndexFragment {
+    PrimitiveType type;
+    ushort start;
+    ushort end;
+    this(PrimitiveType type, int start, int end) {
+        this.type = type;
+        this.start = cast(ushort)start;
+        this.end = cast(ushort)end;
+    }
+}
+
 /// Mesh
 class Mesh {
     protected VertexFormat _vertexFormat;
     protected int _vertexCount;
     protected float[] _vertexData;
     protected MeshPart[] _parts;
+    protected VertexBuffer _vertexBuffer;
 
     @property ref const(VertexFormat) vertexFormat() const { return _vertexFormat; }
 
@@ -141,6 +165,7 @@ class Mesh {
         assert(_vertexCount == 0);
         _vertexFormat = format; 
     }
+
     /// returns vertex count
     @property int vertexCount() const { return _vertexCount; }
 
@@ -166,6 +191,34 @@ class Mesh {
         return res;
     }
 
+    /// list of mesh fragments
+    @property IndexFragment[] indexFragments() const {
+        IndexFragment[] res;
+        int pos = 0;
+        foreach(p; _parts) {
+            res ~= IndexFragment(p.type, pos, pos + p.length);
+            pos += p.length;
+        }
+        return res;
+    }
+
+    /// get vertex buffer object
+    @property VertexBuffer vertexBuffer() {
+        return _vertexBuffer;
+    }
+
+    /// set vertex buffer object
+    @property void vertexBuffer(VertexBuffer buffer) {
+        if (_vertexBuffer) {
+            _vertexBuffer.destroy;
+            _vertexBuffer = null;
+        }
+        _vertexBuffer = buffer;
+        if (_vertexBuffer) {
+            _vertexBuffer.setData(this);
+        }
+    }
+
     /// mesh part count
     @property int partCount() const { return cast(int)_parts.length; }
     /// returns mesh part by index
@@ -206,15 +259,13 @@ class Mesh {
     this(VertexFormat vertexFormat) {
         _vertexFormat = vertexFormat;
     }
-}
 
-/// Graphics primitive type
-enum PrimitiveType : int {
-    triangles,
-    triangleStripes,
-    lines,
-    lineStripes,
-    points,
+    ~this() {
+        if (_vertexBuffer) {
+            _vertexBuffer.destroy;
+            _vertexBuffer = null;
+        }
+    }
 }
 
 /// Mesh part - set of vertex indexes with graphics primitive type