2 files changed, 68 insertions, 0 deletions

diff --git a/src/render/modernopenglgraphics.cpp b/src/render/modernopenglgraphics.cpp
index 3d4cf68a1..e92002e92 100644
--- a/src/render/modernopenglgraphics.cpp
+++ b/src/render/modernopenglgraphics.cpp
@@ -903,6 +903,62 @@ bool ModernOpenGLGraphics::drawNet(const int x1, const int y1,
                                    const int x2, const int y2,
                                    const int width, const int height)
 {
+    unsigned int vp = 0;
+    const unsigned int vLimit = mMaxVertices * 4;
+
+    setTexturingAndBlending(false);
+    const ClipRect &clipArea = mClipStack.top();
+    const GLfloat dx = clipArea.xOffset;
+    const GLfloat dy = clipArea.yOffset;
+
+    const GLfloat xs1 = static_cast<GLfloat>(x1) + dx;
+    const GLfloat xs2 = static_cast<GLfloat>(x2) + dx;
+    const GLfloat ys1 = static_cast<GLfloat>(y1) + dy;
+    const GLfloat ys2 = static_cast<GLfloat>(y2) + dy;
+
+    for (int y = y1; y < y2; y += height)
+    {
+        mFloatArray[vp + 0] = xs1;
+        mFloatArray[vp + 1] = y;
+        mFloatArray[vp + 2] = 0.0f;
+        mFloatArray[vp + 3] = 0.0f;
+
+        mFloatArray[vp + 4] = xs2;
+        mFloatArray[vp + 5] = y;
+        mFloatArray[vp + 6] = 0.0f;
+        mFloatArray[vp + 7] = 0.0f;
+
+        vp += 8;
+        if (vp >= vLimit)
+        {
+            drawLineArrays(vp);
+            vp = 0;
+        }
+    }
+
+    for (int x = x1; x < x2; x += width)
+    {
+        mFloatArray[vp + 0] = x;
+        mFloatArray[vp + 1] = ys1;
+        mFloatArray[vp + 2] = 0.0f;
+        mFloatArray[vp + 3] = 0.0f;
+
+        mFloatArray[vp + 4] = x;
+        mFloatArray[vp + 5] = ys2;
+        mFloatArray[vp + 6] = 0.0f;
+        mFloatArray[vp + 7] = 0.0f;
+
+        vp += 8;
+        if (vp >= vLimit)
+        {
+            drawLineArrays(vp);
+            vp = 0;
+        }
+    }
+
+    if (vp > 0)
+        drawLineArrays(vp);
+
     return true;
 }
 
@@ -964,6 +1020,16 @@ void ModernOpenGLGraphics::drawTriangleArray(const int size)
     glDrawArrays(GL_TRIANGLES, 0, size / 4);
 }
 
+void ModernOpenGLGraphics::drawLineArrays(const int size)
+{
+    mglBufferData(GL_ARRAY_BUFFER, size * sizeof(GLfloat),
+        mFloatArray, GL_DYNAMIC_DRAW);
+#ifdef DEBUG_DRAW_CALLS
+    mDrawCalls ++;
+#endif
+    glDrawArrays(GL_LINES, 0, size / 4);
+}
+
 #ifdef DEBUG_BIND_TEXTURE
 void ModernOpenGLGraphics::debugBindTexture(const Image *const image)
 {
diff --git a/src/render/modernopenglgraphics.h b/src/render/modernopenglgraphics.h
index fec209a7e..3528462a8 100644
--- a/src/render/modernopenglgraphics.h
+++ b/src/render/modernopenglgraphics.h
@@ -87,6 +87,8 @@ class ModernOpenGLGraphics final : public Graphics
 
         inline void drawTriangleArray(const int size);
 
+        inline void drawLineArrays(const int size);
+
         GLfloat *mFloatArray;
         GLfloat *mFloatArrayCached;
         ShaderProgram *mProgram;