logicsignal.cpp

   1 /*
   2  * This file is part of the sigrok project.
   3  *
   4  * Copyright (C) 2012 Joel Holdsworth <joel@airwebreathe.org.uk>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
  19  */
  20
  21 #define GL_GLEXT_PROTOTYPES
  22 #include <GL/gl.h>
  23 #include <GL/glext.h>
  24
  25 #include <math.h>
  26
  27 #include "extdef.h"
  28
  29 #include "logicdata.h"
  30 #include "logicdatasnapshot.h"
  31 #include "logicsignal.h"
  32
  33 using namespace boost;
  34 using namespace std;
  35
  36 const float Log2 = logf(2.0f);
  37
  38 const float LogicSignal::Margin = 10.0f;
  39
  40 const float LogicSignal::EdgeColour[3] =        {0.50f, 0.50f, 0.50f};
  41 const float LogicSignal::HighColour[3] =        {0.00f, 0.75f, 0.00f};
  42 const float LogicSignal::LowColour[3] = {0.75f, 0.00f, 0.00f};
  43
  44 const QColor LogicSignal::LogicSignalColours[10] = {
  45         QColor(0x16, 0x19, 0x1A),       // Black
  46         QColor(0x8F, 0x52, 0x02),       // Brown
  47         QColor(0xCC, 0x00, 0x00),       // Red
  48         QColor(0xF5, 0x79, 0x00),       // Orange
  49         QColor(0xED, 0xD4, 0x00),       // Yellow
  50         QColor(0x73, 0xD2, 0x16),       // Green
  51         QColor(0x34, 0x65, 0xA4),       // Blue
  52         QColor(0x75, 0x50, 0x7B),       // Violet
  53         QColor(0x88, 0x8A, 0x85),       // Grey
  54         QColor(0xEE, 0xEE, 0xEC),       // White
  55 };
  56
  57 LogicSignal::LogicSignal(QString name, shared_ptr<LogicData> data,
  58         int probe_index) :
  59         Signal(name),
  60         _data(data),
  61         _probe_index(probe_index)
  62 {
  63         assert(_probe_index >= 0);
  64 }
  65
  66 void LogicSignal::paint(QGLWidget &widget, const QRect &rect,
  67         double scale, double offset)
  68 {
  69         Point2F *vertex;
  70
  71         vector< pair<int64_t, bool> > edges;
  72
  73         assert(scale > 0);
  74         assert(_data);
  75
  76         const float high_offset = rect.top() + Margin;
  77         const float low_offset = rect.bottom() - Margin;
  78
  79         const queue< shared_ptr<LogicDataSnapshot> > &snapshots =
  80                 _data->get_snapshots();
  81         if(snapshots.empty())
  82                 return;
  83
  84         const shared_ptr<LogicDataSnapshot> &snapshot = snapshots.front();
  85
  86         const double pixels_offset = offset / scale;
  87         const double samplerate = _data->get_samplerate();
  88         const double start_time = _data->get_start_time();
  89         const int64_t last_sample = (int64_t)snapshot->get_sample_count() - 1;
  90         const double samples_per_pixel = samplerate * scale;
  91         const int64_t start = min(max((int64_t)(samplerate * (offset - start_time)),
  92                 (int64_t)0), last_sample);
  93         const int64_t end = min((int64_t)(start + samples_per_pixel * rect.width()),
  94                 last_sample);
  95         const int64_t quantization_length = 1LL << (int64_t)floorf(
  96                 max(logf(samples_per_pixel / Log2), 0.0f));
  97
  98         snapshot->get_subsampled_edges(edges, start, end,
  99                 quantization_length, _probe_index);
 100
 101         // Paint the edges
 102         const unsigned int edge_point_count = (edges.size() - 2) * 2;
 103         Point2F *const edge_points = new Point2F[edge_point_count];
 104         vertex = edge_points;
 105
 106         for(vector<LogicDataSnapshot::EdgePair>::const_iterator i = edges.begin() + 1;
 107             i != edges.end() - 1; i++)
 108         {
 109                 const int x = (int)((*i).first / samples_per_pixel - pixels_offset) +
 110                         rect.left();
 111
 112                 vertex->x = x, vertex->y = high_offset;
 113                 vertex++;
 114                 vertex->x = x, vertex->y = low_offset;
 115                 vertex++;
 116         }
 117
 118         glColor3fv(EdgeColour);
 119         paint_lines(edge_points, edge_point_count);
 120         delete[] edge_points;
 121
 122         // Paint the caps
 123         const unsigned int max_cap_point_count = (edges.size() - 1) * 2;
 124         Point2F *const cap_points = new Point2F[max_cap_point_count];
 125
 126         glColor3fv(HighColour);
 127         paint_caps(cap_points, edges, true, samples_per_pixel,
 128                 pixels_offset, rect.left(), high_offset);
 129         glColor3fv(LowColour);
 130         paint_caps(cap_points, edges, false, samples_per_pixel,
 131                 pixels_offset, rect.left(), low_offset);
 132
 133         delete[] cap_points;
 134 }
 135
 136 int LogicSignal::paint_caps(Point2F *const cap_points,
 137         vector< pair<int64_t, bool> > &edges, bool level,
 138         double samples_per_pixel, double pixels_offset, int x_offset,
 139         int y_offset)
 140 {
 141         Point2F *vertex = cap_points;
 142
 143         for(vector<LogicDataSnapshot::EdgePair>::const_iterator i = edges.begin();
 144             i != (edges.end() - 1); i++)
 145                 if((*i).second == level)
 146                 {
 147                         vertex->x = (int)((*i).first / samples_per_pixel -
 148                                 pixels_offset) + x_offset - 1;
 149                         vertex->y = y_offset;
 150                         vertex++;
 151
 152                         vertex->x = (int)((*(i+1)).first / samples_per_pixel -
 153                                 pixels_offset) + x_offset;
 154                         vertex->y = y_offset;
 155                         vertex++;
 156                 }
 157
 158         paint_lines(cap_points, vertex - cap_points);
 159 }
 160
 161 void LogicSignal::paint_lines(Point2F *points, int count)
 162 {
 163         GLuint vbo_id;
 164
 165         assert(points);
 166
 167         glGenBuffers(1, &vbo_id);
 168         glBindBuffer(GL_ARRAY_BUFFER, vbo_id);
 169
 170         const unsigned int vbo_length = count * sizeof(Point2F);
 171         glBufferData(GL_ARRAY_BUFFER, vbo_length, NULL, GL_STATIC_DRAW);
 172         glBufferSubData(GL_ARRAY_BUFFER, 0, vbo_length, points);
 173
 174         glBindBuffer(GL_ARRAY_BUFFER, vbo_id);
 175
 176         glVertexPointer(2, GL_FLOAT, sizeof(Point2F), 0);
 177
 178         glEnableClientState(GL_VERTEX_ARRAY);
 179         glDrawArrays(GL_LINES,  0,  count);
 180         glDisableClientState(GL_VERTEX_ARRAY);
 181
 182         glDeleteBuffers(1, &vbo_id);
 183 }
 184
 185 QColor LogicSignal::get_colour() const
 186 {
 187         return LogicSignalColours[_probe_index % countof(LogicSignalColours)];
 188 }
 189
 190 int LogicSignal::get_nominal_offset(const QRect &rect) const
 191 {
 192         return rect.bottom() - Margin;
 193 }