Merge pull request #160 from mcjohnalds/text-annotations

Added billboard text annotations

shaders/annotation.glsl

@@ -0,0 +1,49 @@
+#version 150
+// Copyright 2015, Christopher J. Foster and the other displaz contributors.
+// Use of this code is governed by the BSD-style license found in LICENSE.txt
+
+// Draws annotations, which are textured quads that always face the camera,
+// arent't obscured by other objects, and don't shrink when they're further
+// away.
+
+uniform mat4 modelViewMatrix;
+uniform mat4 projectionMatrix;
+uniform mat4 modelViewProjectionMatrix;
+uniform vec2 annotationSize; // In pixels
+uniform vec2 viewportSize; // In pixels
+
+//------------------------------------------------------------------------------
+#if defined(VERTEX_SHADER)
+
+// Position of the current quad vertex. The bottom-left vertex is at (-1,-1)
+// and the top-right at (1,1).
+in vec2 position;
+in vec2 texCoord;
+
+out vec2 ftexCoord;
+
+void main()
+{
+    gl_Position = modelViewProjectionMatrix * vec4(0, 0, 0, 1.0);
+    gl_Position /= gl_Position.w;
+    gl_Position.xy += position * annotationSize / viewportSize;
+    ftexCoord = texCoord;
+}
+
+
+//------------------------------------------------------------------------------
+#elif defined(FRAGMENT_SHADER)
+
+uniform sampler2D texture0;
+
+in vec2 ftexCoord;
+
+// Output fragment color
+out vec4 fragColor;
+
+void main()
+{
+    fragColor = texture(texture0, vec2(ftexCoord));
+}
+
+#endif

src/CMakeLists.txt

@@ -114,6 +114,7 @@ set(gui_srcs
     render/View3D.cpp
     render/Shader.cpp
     render/GeometryMutator.cpp
+    render/Annotation.cpp
 
     ../thirdparty/rply/rply.c
     ../thirdparty/polypartition/polypartition.cpp

src/geometrycollection.h

@@ -58,7 +58,6 @@ class GeometryCollection : public QAbstractListModel
         void addGeometry(std::shared_ptr<Geometry> geom, bool replaceLabel = false, bool reloaded = false);
         void mutateGeometry(std::shared_ptr<GeometryMutator> mutator);
 
-
     private:
         void loadPointFilesImpl(const QStringList& fileNames, bool removeAfterLoad);
         int findMatchingRow(const QRegExp & filenameRegex);

src/gui/PointViewerMainWindow.cpp

@@ -159,6 +159,9 @@ PointViewerMainWindow::PointViewerMainWindow(const QGLFormat& format)
     QAction* drawGrid = viewMenu->addAction(tr("Draw &Grid"));
     drawGrid->setCheckable(true);
     drawGrid->setChecked(false);
+    QAction* drawAnnotations = viewMenu->addAction(tr("Draw A&nnotations"));
+    drawAnnotations->setCheckable(true);
+    drawAnnotations->setChecked(true);
 
     // Shader menu
     QMenu* shaderMenu = menuBar()->addMenu(tr("&Shader"));
@@ -193,6 +196,8 @@ PointViewerMainWindow::PointViewerMainWindow(const QGLFormat& format)
             m_pointView, SLOT(toggleDrawAxes()));
     connect(drawGrid, SIGNAL(triggered()),
             m_pointView, SLOT(toggleDrawGrid()));
+    connect(drawAnnotations, SIGNAL(triggered()),
+            m_pointView, SLOT(toggleDrawAnnotations()));
     connect(trackballMode, SIGNAL(triggered()),
             m_pointView, SLOT(toggleCameraMode()));
     connect(m_geometries, SIGNAL(rowsInserted(QModelIndex,int,int)),
@@ -400,6 +405,7 @@ void PointViewerMainWindow::handleMessage(QByteArray message)
             return;
         }
         m_geometries->unloadFiles(regex);
+        m_pointView->removeAnnotations(regex);
     }
     else if (commandTokens[0] == "SET_VIEW_LABEL")
     {
@@ -415,6 +421,27 @@ void PointViewerMainWindow::handleMessage(QByteArray message)
         if (index.isValid())
             m_pointView->centerOnGeometry(index);
     }
+    else if (commandTokens[0] == "ANNOTATE")
+    {
+        if (commandTokens.size() - 1 != 5)
+        {
+            tfm::format(std::cerr, "Expected five arguments, got %d\n",
+                        commandTokens.size() - 1);
+            return;
+        }
+        QString label = commandTokens[1];
+        QString text = commandTokens[2];
+        bool xOk = false, yOk = false, zOk = false;
+        double x = commandTokens[3].toDouble(&xOk);
+        double y = commandTokens[4].toDouble(&yOk);
+        double z = commandTokens[5].toDouble(&zOk);
+        if (!zOk || !yOk || !zOk)
+        {
+            std::cerr << "Could not parse XYZ coordinates for position\n";
+            return;
+        }
+        m_pointView->addAnnotation(label, text, Imath::V3d(x, y, z));
+    }
     else if (commandTokens[0] == "SET_VIEW_POSITION")
     {
         if (commandTokens.size()-1 != 3)

src/main.cpp

@@ -60,13 +60,17 @@ int main(int argc, char *argv[])
     double viewRadius = -DBL_MAX;
 
     std::string shaderName;
-    std::string unloadFiles;
+    std::string unloadRegex;
     std::string viewLabelName;
     bool noServer = false;
 
     bool clearFiles = false;
     bool addFiles = false;
     bool mutateData = false;
+    std::string annotationText;
+    double annotationX = -DBL_MAX;
+    double annotationY = -DBL_MAX;
+    double annotationZ = -DBL_MAX;
     bool deleteAfterLoad = false;
     bool quitRemote = false;
     bool queryCursor = false;
@@ -109,10 +113,11 @@ int main(int argc, char *argv[])
                                          "This alternative to -viewangles is supplied to simplify "
                                          "setting camera rotations from a script.",
         "-clear",        &clearFiles,    "Remote: clear all currently loaded files",
-        "-unload %s",    &unloadFiles,   "Remote: unload loaded files matching the given (unix shell style) pattern",
+        "-unload %s",    &unloadRegex,   "Remote: unload loaded files or annotations who's label matches the given (unix shell style) pattern",
         "-quit",         &quitRemote,    "Remote: close the existing displaz window",
         "-add",          &addFiles,      "Remote: add files to currently open set, instead of replacing those with duplicate labels",
         "-modify",       &mutateData,    "Remote: mutate data already loaded with the matching label (requires displaz .ply with an \"index\" field to indicate mutated points)",
+        "-annotation %s %F %F %F", &annotationText, &annotationX, &annotationY, &annotationZ, "Add a text annotation [text, x, y, z]",
         "-rmtemp",       &deleteAfterLoad, "*Delete* files after loading - use with caution to clean up single-use temporary files after loading",
         "-querycursor",  &queryCursor,   "Query 3D cursor location from displaz instance",
         "-script",       &script,        "Script mode: enable several settings which are useful when calling displaz from a script:"
@@ -175,7 +180,7 @@ int main(int argc, char *argv[])
             std::cerr << "ERROR: No remote displaz instance found\n";
             return EXIT_FAILURE;
         }
-        if (quitRemote || !unloadFiles.empty())
+        if (quitRemote || !unloadRegex.empty())
         {
             return EXIT_SUCCESS;
         }
@@ -244,9 +249,21 @@ int main(int argc, char *argv[])
         }
         channel->sendMessage(command);
     }
-    if (!unloadFiles.empty())
+    if (annotationText != "" &&
+        annotationX != -DBL_MAX &&
+        annotationY != -DBL_MAX &&
+        annotationZ != -DBL_MAX)
     {
-        channel->sendMessage(QByteArray("UNLOAD_FILES\n") + unloadFiles.c_str());
+        channel->sendMessage(QByteArray("ANNOTATE\n") +
+                             g_dataSetLabel.c_str() + "\n" +
+                             annotationText.c_str() + "\n" +
+                             QByteArray().setNum(annotationX, 'e', 17) + "\n" +
+                             QByteArray().setNum(annotationY, 'e', 17) + "\n" +
+                             QByteArray().setNum(annotationZ, 'e', 17));
+    }
+    if (!unloadRegex.empty())
+    {
+        channel->sendMessage(QByteArray("UNLOAD_FILES\n") + unloadRegex.c_str());
     }
     if (!viewLabelName.empty())
     {

src/render/Annotation.cpp

@@ -0,0 +1,122 @@
+// Copyright 2015, Christopher J. Foster and the other displaz contributors.
+// Use of this code is governed by the BSD-style license found in LICENSE.txt
+
+#include "Annotation.h"
+
+#include <cmath>
+
+#include <QFont>
+#include <QFontMetrics>
+#include <QColor>
+#include <QImage>
+#include <QPainter>
+
+/// Creates and returns a texture containing some text.
+static std::unique_ptr<Texture> makeTextureFromText(const QString& text)
+{
+    QFont font("Sans", 13);
+    // Text outline makes the text thinner so we have to bold it
+    font.setWeight(QFont::DemiBold);
+    QFontMetrics fm(font);
+    int width = fm.width(text);
+    int height = fm.ascent() + fm.descent();
+    QImage image(width, height, QImage::Format_RGBA8888);
+    image.fill(Qt::transparent);
+    QPainter painter(&image);
+    painter.setRenderHint(QPainter::Antialiasing, true);
+    painter.setRenderHint(QPainter::TextAntialiasing, true);
+    painter.translate(0, height + fm.descent());
+    painter.scale(1, -1);
+    painter.setBrush(Qt::white);
+    // Add a black outline for visibility when on a white background
+    QPen pen;
+    pen.setWidthF(1.2);
+    pen.setColor(Qt::black);
+    painter.setPen(pen);
+    QPainterPath path;
+    path.addText(0, height, font, text);
+    painter.drawPath(path);
+    std::unique_ptr<Texture> texture(new Texture(image));
+    // The text is blurry when using GL_LINEAR. I suspect this is a result of
+    // floating point inaccuracies in the vertex shader.
+    texture->setResizeFilter(GL_NEAREST);
+    return texture;
+}
+
+/// Creates a texturable rectangle VAO and returns it's name.
+static GLuint makeVAO(GLuint annotationShaderProg)
+{
+    GLuint vao;
+    glGenVertexArrays(1, &vao);
+    glBindVertexArray(vao);
+
+    // Setup buffer
+    GlBuffer buffer;
+    buffer.bind(GL_ARRAY_BUFFER);
+    float data[] = { // x,  y, s, t
+                       -1, -1, 0, 0, // bottom-left
+                        1, -1, 1, 0, // bottom-right
+                       -1,  1, 0, 1, // top-left
+                        1,  1, 1, 1, }; // top-right
+    size_t rowSize = sizeof (float) * 4;
+    size_t xyzOffset = 0;
+    size_t stOffset = sizeof (float) * 2;
+    glBufferData(GL_ARRAY_BUFFER, sizeof data, data, GL_STATIC_DRAW);
+
+    // Setup attributes
+    GLint positionAttribute = glGetAttribLocation(annotationShaderProg, "position");
+    glVertexAttribPointer(positionAttribute,
+                          2,
+                          GL_FLOAT,
+                          GL_FALSE,
+                          rowSize,
+                          (void*) xyzOffset);
+    glEnableVertexAttribArray(positionAttribute);
+
+    GLint texCoordAttribute = glGetAttribLocation(annotationShaderProg, "texCoord");
+    glVertexAttribPointer(texCoordAttribute,
+                          2,
+                          GL_FLOAT,
+                          GL_FALSE,
+                          rowSize,
+                          (void*) stOffset);
+    glEnableVertexAttribArray(texCoordAttribute);
+
+    glBindBuffer(GL_ARRAY_BUFFER, 0);
+    glBindVertexArray(0);
+    return vao;
+}
+
+Annotation::Annotation(const QString& label,
+                       GLuint annotationShaderProg,
+                       const QString& text,
+                       Imath::V3d position)
+     : m_label(label),
+     m_text(text),
+     m_position(position),
+     m_texture(makeTextureFromText(text)),
+     m_vao(makeVAO(annotationShaderProg))
+{
+}
+
+Annotation::~Annotation()
+{
+    glDeleteVertexArrays(1, &m_vao);
+}
+
+void Annotation::draw(QGLShaderProgram& annotationShaderProg,
+                      const TransformState& transState) const
+{
+    glBindVertexArray(m_vao);
+    GLint texture0 = glGetUniformLocation(annotationShaderProg.programId(),
+                                          "texture0");
+    m_texture->bind(texture0);
+    annotationShaderProg.setUniformValue("annotationSize",
+                                        m_texture->width(),
+                                        m_texture->height());
+    transState.translate(m_position)
+              .setUniforms(annotationShaderProg.programId());
+    glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
+    glBindTexture(GL_TEXTURE_2D, 0);
+    glBindVertexArray(0);
+}

src/render/Annotation.h

@@ -0,0 +1,47 @@
+// Copyright 2015, Christopher J. Foster and the other displaz contributors.
+// Use of this code is governed by the BSD-style license found in LICENSE.txt
+
+#ifndef DISPLAZ_ANNOTATION_H_INCLUDED
+#define DISPLAZ_ANNOTATION_H_INCLUDED
+
+#include <memory>
+
+#include "glutil.h"
+#include <QString>
+#include <QGLShaderProgram>
+
+struct TransformState;
+
+/// Annotations display text, always face the camera, and aren't obscured by
+/// other objects
+class Annotation
+{
+
+    public:
+        Annotation(const QString& label,
+                   GLuint annotationShaderProg,
+                   const QString& text,
+                   Imath::V3d position);
+
+        ~Annotation();
+
+        QString label() const { return m_label; }
+
+        /// Draw the annotation using the given shader program
+        ///
+        /// Requires that `annotationShaderProg` is already bound and that
+        /// the viewportSize uniform variable has been set.
+        ///
+        /// transState specifies the camera transform.
+        void draw(QGLShaderProgram& annotationShaderProg,
+                  const TransformState& transState) const;
+
+    private:
+        QString m_label;
+        QString m_text;
+        Imath::V3d m_position;
+        std::shared_ptr<Texture> m_texture;
+        GLuint m_vao;
+};
+
+#endif // DISPLAZ_ANNOTATION_H_INCLUDED

src/render/Geometry.h

@@ -65,7 +65,7 @@ class Geometry : public QObject
         //--------------------------------------------------
         /// Mutate a geometry
         ///
-        /// Apply a per-vertex modification of geometry data with the data in a 
+        /// Apply a per-vertex modification of geometry data with the data in a
         /// GeometryMutator, which keeps an index to a subset of vertices and
         /// new data for a subset of fields. The number of vertices remains
         /// constant.