CubicSDR/src/PrimaryGLContext.cpp

#include "PrimaryGLContext.h"

#include "wx/wxprec.h"

#ifndef WX_PRECOMP
#include "wx/wx.h"
#endif

#if !wxUSE_GLCANVAS
#error "OpenGL required: set wxUSE_GLCANVAS to 1 and rebuild the library"
#endif

#include "CubicSDR.h"

wxString glGetwxString(GLenum name) {
    const GLubyte *v = glGetString(name);
    if (v == 0) {
        // The error is not important. It is GL_INVALID_ENUM.
        // We just want to clear the error stack.
        glGetError();

        return wxString();
    }

    return wxString((const char*) v);
}

static void CheckGLError() {
    GLenum errLast = GL_NO_ERROR;

    for (;;) {
        GLenum err = glGetError();
        if (err == GL_NO_ERROR)
            return;

        if (err == errLast) {
            wxLogError
            (wxT("OpenGL error state couldn't be reset."));
            return;
        }

        errLast = err;

        wxLogError
        (wxT("OpenGL error %d"), err);
    }
}

PrimaryGLContext::PrimaryGLContext(wxGLCanvas *canvas) :
        wxGLContext(canvas) {
    SetCurrent(*canvas);

    glEnable(GL_CULL_FACE);
    glEnable(GL_DEPTH_TEST);

    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();

    CheckGLError();
}

void PrimaryGLContext::PlotIQ(std::vector<float> &i_points, std::vector<float> &q_points) {
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();

    glPushMatrix();
    glTranslatef(0.0f, 0.5f, 0.0f);
    if (q_points.size()) {
        glScalef(10.0f, 1.0f, 1.0f);
        glEnableClientState(GL_VERTEX_ARRAY);
        glVertexPointer(2, GL_FLOAT, 0, &q_points[0]);
        glDrawArrays(GL_LINE_STRIP, 0, q_points.size() / 2);
        glDisableClientState(GL_VERTEX_ARRAY);
    } else {
        glBegin(GL_LINE_STRIP);
        glColor3f(1.0f, 1.0f, 1.0f);
        glVertex3f(-1.0f, 0.0f, 0.0f);
        glVertex3f(1.0f, 0.0f, 0.0f);
        glEnd();
    }
    glPopMatrix();

    glPushMatrix();
    glTranslatef(0.0f, -0.5f, 0.0f);
    if (i_points.size()) {
        glScalef(10.0f, 1.0f, 1.0f);
        glEnableClientState(GL_VERTEX_ARRAY);
        glVertexPointer(2, GL_FLOAT, 0, &i_points[0]);
        glDrawArrays(GL_LINE_STRIP, 0, i_points.size() / 2);
        glDisableClientState(GL_VERTEX_ARRAY);
    } else {
        glBegin(GL_LINE_STRIP);
        glColor3f(1.0f, 1.0f, 1.0f);
        glVertex3f(-1.0f, 0.0f, 0.0f);
        glVertex3f(1.0f, 0.0f, 0.0f);
        glEnd();
    }
    glPopMatrix();

    glFlush();

    CheckGLError();
}

wxBEGIN_EVENT_TABLE(TestGLCanvas, wxGLCanvas) EVT_PAINT(TestGLCanvas::OnPaint)
EVT_KEY_DOWN(TestGLCanvas::OnKeyDown)
EVT_IDLE(TestGLCanvas::OnIdle)
wxEND_EVENT_TABLE()

TestGLCanvas::TestGLCanvas(wxWindow *parent, int *attribList) :
        wxGLCanvas(parent, wxID_ANY, attribList, wxDefaultPosition, wxDefaultSize,
        wxFULL_REPAINT_ON_RESIZE) {

}

void TestGLCanvas::OnPaint(wxPaintEvent& WXUNUSED(event)) {
    wxPaintDC dc(this);
    const wxSize ClientSize = GetClientSize();

    PrimaryGLContext& canvas = wxGetApp().GetContext(this);
    glViewport(0, 0, ClientSize.x, ClientSize.y);

    canvas.PlotIQ(i_points, q_points);

    SwapBuffers();
}

void TestGLCanvas::OnKeyDown(wxKeyEvent& event) {
    float angle = 5.0;

    switch (event.GetKeyCode()) {
    case WXK_RIGHT:
        break;
    case WXK_LEFT:
        break;
    case WXK_DOWN:
        break;
    case WXK_UP:
        break;
    case WXK_SPACE:
        break;
    default:
        event.Skip();
        return;
    }
}

void TestGLCanvas::setData(std::vector<signed char> *data) {
    if (data && data->size()) {
        if (i_points.size() < data->size()) {
            i_points.resize(data->size());
        }
        if (q_points.size() < data->size()) {
            q_points.resize(data->size());
        }

        for (int i = 0, iMax = data->size() / 2; i < iMax; i++) {
            i_points[i * 2 + 1] = (float) (*data)[i * 2] / 127.0f;
            q_points[i * 2 + 1] = (float) (*data)[i * 2 + 1] / 127.0f;
            i_points[i * 2] = q_points[i * 2] = 2.0f * ((float) i / (float) iMax) - 1.0f;
        }
    }
}

void TestGLCanvas::OnIdle(wxIdleEvent &event) {
    Refresh(false);
}
;