From 2ebca0a659c6ceb2ed6a3046cec8defb14d2b0eb Mon Sep 17 00:00:00 2001
From: Ryan Huffman <ryanhuffman@gmail.com>
Date: Tue, 11 Nov 2014 09:50:25 -0800
Subject: [PATCH] Add Grid3DOverlay

---
 interface/src/ui/overlays/Grid3DOverlay.cpp | 118 ++++++++++++++++++++
 interface/src/ui/overlays/Grid3DOverlay.h   |  44 ++++++++
 2 files changed, 162 insertions(+)
 create mode 100644 interface/src/ui/overlays/Grid3DOverlay.cpp
 create mode 100644 interface/src/ui/overlays/Grid3DOverlay.h

diff --git a/interface/src/ui/overlays/Grid3DOverlay.cpp b/interface/src/ui/overlays/Grid3DOverlay.cpp
new file mode 100644
index 0000000000..c628199fe3
--- /dev/null
+++ b/interface/src/ui/overlays/Grid3DOverlay.cpp
@@ -0,0 +1,118 @@
+//
+//  Grid3DOverlay.cpp
+//  interface/src/ui/overlays
+//
+//  Created by Ryan Huffman on 11/06/14.
+//  Copyright 2014 High Fidelity, Inc.
+//
+//  Distributed under the Apache License, Version 2.0.
+//  See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
+//
+
+#include "Grid3DOverlay.h"
+
+#include "Application.h"
+
+ProgramObject Grid3DOverlay::_gridProgram;
+
+Grid3DOverlay::Grid3DOverlay() : Base3DOverlay(),
+    _minorGridWidth(1.0),
+    _majorGridEvery(5) {
+}
+
+Grid3DOverlay::~Grid3DOverlay() {
+}
+
+void Grid3DOverlay::render(RenderArgs* args) {
+    if (!_visible) {
+        return; // do nothing if we're not visible
+    }
+
+    if (!_gridProgram.isLinked()) {
+        if (!_gridProgram.addShaderFromSourceFile(QGLShader::Fragment, Application::resourcesPath() + "shaders/grid.frag")) {
+            qDebug() << "Failed to compile: " + _gridProgram.log();
+            return;
+        }
+        if (!_gridProgram.link()) {
+            qDebug() << "Failed to link: " + _gridProgram.log();
+            return;
+        }
+    }
+
+    // Render code largely taken from MetavoxelEditor::render()
+    glDisable(GL_LIGHTING);
+
+    glDepthMask(GL_FALSE);
+
+    glPushMatrix();
+
+    glm::quat rotation = getRotation();
+
+    glm::vec3 axis = glm::axis(rotation);
+
+    glRotatef(glm::degrees(glm::angle(rotation)), axis.x, axis.y, axis.z);
+
+    glLineWidth(1.5f);
+
+    // center the grid around the camera position on the plane
+    glm::vec3 rotated = glm::inverse(rotation) * Application::getInstance()->getCamera()->getPosition();
+    float spacing = _minorGridWidth;
+
+    float alpha = getAlpha();
+    xColor color = getColor();
+    glm::vec3 position = getPosition();
+
+    const int GRID_DIVISIONS = 300;
+    const float MAX_COLOR = 255.0f;
+    float scale = GRID_DIVISIONS * spacing;
+
+    glColor4f(color.red / MAX_COLOR, color.green / MAX_COLOR, color.blue / MAX_COLOR, alpha);
+
+    _gridProgram.bind();
+
+    // Minor grid
+    glPushMatrix();
+    {
+        glTranslatef(_minorGridWidth * (floorf(rotated.x / spacing) - GRID_DIVISIONS / 2),
+            spacing * (floorf(rotated.y / spacing) - GRID_DIVISIONS / 2), position.z);
+
+        glScalef(scale, scale, scale);
+
+        Application::getInstance()->getGeometryCache()->renderGrid(GRID_DIVISIONS, GRID_DIVISIONS);
+    }
+    glPopMatrix();
+
+    // Major grid
+    glPushMatrix();
+    {
+        glLineWidth(4.0f);
+        spacing *= _majorGridEvery;
+        glTranslatef(spacing * (floorf(rotated.x / spacing) - GRID_DIVISIONS / 2),
+            spacing * (floorf(rotated.y / spacing) - GRID_DIVISIONS / 2), position.z);
+
+        scale *= _majorGridEvery;
+        glScalef(scale, scale, scale);
+
+        Application::getInstance()->getGeometryCache()->renderGrid(GRID_DIVISIONS, GRID_DIVISIONS);
+    }
+    glPopMatrix();
+
+    _gridProgram.release();
+
+    glPopMatrix();
+
+    glEnable(GL_LIGHTING);
+    glDepthMask(GL_TRUE);
+}
+
+void Grid3DOverlay::setProperties(const QScriptValue& properties) {
+    Base3DOverlay::setProperties(properties);
+
+    if (properties.property("minorGridWidth").isValid()) {
+        _minorGridWidth = properties.property("minorGridWidth").toVariant().toFloat();
+    }
+
+    if (properties.property("majorGridEvery").isValid()) {
+        _majorGridEvery = properties.property("majorGridEvery").toVariant().toInt();
+    }
+}
diff --git a/interface/src/ui/overlays/Grid3DOverlay.h b/interface/src/ui/overlays/Grid3DOverlay.h
new file mode 100644
index 0000000000..b1675f15d7
--- /dev/null
+++ b/interface/src/ui/overlays/Grid3DOverlay.h
@@ -0,0 +1,44 @@
+//
+//  Grid3DOverlay.h
+//  interface/src/ui/overlays
+//
+//  Created by Ryan Huffman on 11/06/14.
+//  Copyright 2014 High Fidelity, Inc.
+//
+//  Distributed under the Apache License, Version 2.0.
+//  See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
+//
+
+#ifndef hifi_Grid3DOverlay_h
+#define hifi_Grid3DOverlay_h
+
+// include this before QGLWidget, which includes an earlier version of OpenGL
+#include "InterfaceConfig.h"
+
+#include <glm/glm.hpp>
+
+#include <QGLWidget>
+#include <SharedUtil.h>
+
+#include "Base3DOverlay.h"
+
+#include "renderer/ProgramObject.h"
+
+class Grid3DOverlay : public Base3DOverlay {
+    Q_OBJECT
+
+public:
+    Grid3DOverlay();
+    ~Grid3DOverlay();
+
+    virtual void render(RenderArgs* args);
+    virtual void setProperties(const QScriptValue& properties);
+
+private:
+    float _minorGridWidth;
+    int _majorGridEvery;
+
+    static ProgramObject _gridProgram;
+};
+
+#endif // hifi_Grid3DOverlay_h