SpectrumDisplay.cpp

00001 //-------------------------------------------------------
00002 // Class for display spectrum
00003 // Copyright (c) 2014 MIKAMI, Naoki,  2014/12/28
00004 //-------------------------------------------------------
00005 
00006 #include "SpectrumDisplay.hpp"
00007 
00008 namespace Mikami
00009 {
00010     SpectrumDisplay::SpectrumDisplay(
00011             SeeedStudioTFTv2* lcd,
00012             int nFft, int x0, int y0,
00013             float db1, int bin, float maxDb, int fs)
00014         : N_FFT_(nFft), X0_(x0), Y0_(y0),
00015           DB1_(db1), BIN_(bin), MAX_DB_(maxDb), FS_(fs),
00016           lcd_(lcd)
00017     {
00018         lcd_->background(Navy);
00019         lcd_->foreground(White);
00020         lcd_->cls();
00021         lcd_->set_orientation(1);
00022         lcd_->set_font((uint8_t*) Arial12x12);
00023         lcd_->locate(86,3);
00024         lcd_->printf("Spectrum Analyzer");
00025 
00026         AxisX();
00027         AxisY();
00028     }
00029 
00030     void SpectrumDisplay::BarChart(float db[], float offset)
00031     {
00032         for (int n=1; n<=N_FFT_/2; n++)
00033         {
00034             float h = ((db[n] + offset) >= 0)? db[n] + offset : 0;
00035             if (h > MAX_DB_) h = MAX_DB_;
00036             int y = Y0_ - (int)(h*DB1_);
00037             lcd_->line(X0_+n, Y0_-1, X0_+n, y, Cyan);
00038             lcd_->line(X0_+n, y-1, X0_+n, Y0_-(int)(MAX_DB_*DB1_), Navy);
00039         }
00040         lcd_->line(X0_, Y0_, X0_+BIN_*N_FFT_/2, Y0_, Yellow);
00041     }
00042 
00043     void SpectrumDisplay::LineChart(float db[], float offset)
00044     {
00045         lcd_->fillrect(X0_+1, Y0_-(int)(MAX_DB_*DB1_),
00046                        X0_+N_FFT_*BIN_/2, Y0_-1, Navy);
00047 
00048         float db1 = ((db[1] + offset) > 0)? db[1] + offset : 0;
00049         int y1 = Y0_ - (int)(db1*DB1_);
00050         for (int n=1; n<N_FFT_/2; n++)
00051         {
00052             float db2 = ((db[n+1] + offset) > 0)? db[n+1] + offset : 0;
00053             if (db2 > MAX_DB_) db2 = MAX_DB_;
00054             int y2 = Y0_ - (int)(db2*DB1_);
00055             lcd_->line(X0_+n, y1, X0_+n+1, y2, Cyan);
00056             y1 = y2;
00057         }
00058         lcd_->line(X0_, Y0_, X0_+BIN_*N_FFT_/2, Y0_, Yellow);
00059     }
00060 
00061     void SpectrumDisplay::DisplayVolume(float volume)
00062     {
00063         const int X_POS = 305;
00064         const float TH = 0.85f;
00065         if (volume < TH)    // volume < 85 %
00066         {
00067             lcd_->fillrect(X_POS, Y0_-DB1_*MAX_DB_, X_POS+5, Y0_, Navy);
00068             lcd_->fillrect(X_POS, Y0_-DB1_*MAX_DB_*volume,
00069                            X_POS+5, Y0_, Cyan);
00070         }
00071         else                // volume >= 85 %
00072         {
00073             lcd_->fillrect(X_POS, Y0_-DB1_*MAX_DB_, X_POS+5, Y0_, Navy);
00074             lcd_->fillrect(X_POS, Y0_-DB1_*MAX_DB_*volume,
00075                            X_POS+5, Y0_-DB1_*MAX_DB_*TH, Red);
00076             lcd_->fillrect(X_POS, Y0_-DB1_*MAX_DB_*TH, X_POS+5, Y0_, Cyan);
00077         }
00078     }
00079 
00080     // x-axis
00081     void SpectrumDisplay::AxisX()
00082     {
00083         lcd_->line(X0_, Y0_, X0_+BIN_*N_FFT_/2, Y0_, Yellow);
00084         float dx = BIN_*(N_FFT_*1000.0f)/(float)FS_;
00085         for (int n=0; n<=5; n++)
00086         {
00087             int xTick = X0_ + (int)(dx*n + 0.5f);
00088             lcd_->locate(xTick-4, Y0_+10);
00089             lcd_->printf("%d", n);
00090             lcd_->line(xTick, Y0_, xTick, Y0_+5, Yellow);
00091         }
00092         lcd_->locate(110, Y0_+24);
00093         lcd_->printf("Frequency [kHz]");
00094     }
00095 
00096     // y-axis
00097     void SpectrumDisplay::AxisY()
00098     {
00099         lcd_->line(X0_, Y0_+5, X0_, Y0_-(int)(MAX_DB_*DB1_), Yellow);
00100         for (int n=0; n<=(int)MAX_DB_; n+=20)
00101         {
00102             int yTick = Y0_-(int)(DB1_*n);
00103             lcd_->locate(X0_-22, yTick-5);
00104             lcd_->printf("%2d", n);  
00105             lcd_->line(X0_-5, yTick, X0_, yTick, Yellow);
00106         }
00107         lcd_->locate(X0_-27, Y0_-(int)(DB1_*MAX_DB_)-18);
00108         lcd_->printf("[dB]");
00109     }
00110 }