From: sgunderson@bigfoot.com <>
Date: Mon, 19 Jul 2010 21:51:09 +0000 (+0200)
Subject: Make an SDL/OpenGL-frontend; might be more intuitive to read, although I'm not sure... 
X-Git-Url: https://git.sesse.net/?p=pitch;a=commitdiff_plain;h=f5029e9edd2cff89ae9e0ff3d836d871c7c61f95

Make an SDL/OpenGL-frontend; might be more intuitive to read, although I'm not sure about precision.
---

diff --git a/Makefile b/Makefile
index 9f3a83f..3ba2c2f 100644
--- a/Makefile
+++ b/Makefile
@@ -1,11 +1,14 @@
 CXXFLAGS=-g -Wall
-CPPFLAGS=
+CPPFLAGS=$(shell sdl-config --cflags)
 
-all: pitch
+all: pitch glpitch
 clean:
-	$(RM) pitch pitch.o pitchdetector.o linux_audio.o
+	$(RM) pitch glpitch pitch.o glpitch.o pitchdetector.o linux_audio.o
 
 pitch: pitch.o pitchdetector.o linux_audio.o
 	$(CXX) -o pitch pitch.o pitchdetector.o linux_audio.o -lfftw3
 
+glpitch: glpitch.o pitchdetector.o linux_audio.o
+	$(CXX) -o glpitch glpitch.o pitchdetector.o linux_audio.o $(shell sdl-config --libs) -lfftw3 -lGL
+
 .PHONY: clean
diff --git a/glpitch.cpp b/glpitch.cpp
new file mode 100644
index 0000000..90c47b8
--- /dev/null
+++ b/glpitch.cpp
@@ -0,0 +1,76 @@
+#include <SDL.h>
+#include <GL/gl.h>
+
+#include "config.h"
+#include "linux_audio.h"
+#include "notes.h"
+#include "pitchdetector.h"
+
+#define MIN_X -40
+#define MAX_X 5
+
+double find_pos(double freq)
+{
+	return 12.0 * log2(freq / BASE_PITCH) - 3.0;
+}
+
+int main(void)
+{
+	PitchDetector pd(SAMPLE_RATE, FFT_LENGTH, PAD_FACTOR, OVERLAP);
+	int fd = get_dsp_fd(SAMPLE_RATE, FFT_LENGTH, OVERLAP);
+
+	SDL_Init(SDL_INIT_VIDEO);
+	SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
+	SDL_SetVideoMode(1024, 200, 32, SDL_OPENGL);
+
+	glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
+	glClear(GL_COLOR_BUFFER_BIT);
+
+	for ( ;; ) {
+		short buf[FFT_LENGTH / PAD_FACTOR / OVERLAP];
+		read_chunk(fd, buf, FFT_LENGTH / PAD_FACTOR / OVERLAP);
+		std::pair<double, double> peak = pd.detect_pitch(buf);
+
+		glMatrixMode(GL_PROJECTION);
+		glLoadIdentity();
+		glOrtho(MIN_X, MAX_X, 1.0f, 0.0f, 0.0f, 1.0f);
+
+		glMatrixMode(GL_MODELVIEW);
+		glLoadIdentity();
+
+		glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+		glEnable(GL_BLEND); 
+
+		glBegin(GL_QUADS);	
+		glColor4f(0.0, 0.0f, 0.0f, 0.05f);
+		glVertex2f(MIN_X, 0.0f);
+		glVertex2f(MIN_X, 1.0f);
+		glVertex2f(MAX_X, 1.0f);
+		glVertex2f(MAX_X, 0.0f);
+		glEnd();
+
+		glBlendFunc(GL_SRC_ALPHA, GL_ONE);
+
+		double peak_pos = find_pos(peak.first);
+
+		glBegin(GL_QUADS);	
+		glColor4f(0.0, 1.0f, 0.0f, 0.2f);
+		glVertex2f(peak_pos - 0.1, 0.0f);
+		glVertex2f(peak_pos - 0.1, 1.0f);
+		glVertex2f(peak_pos + 0.1, 1.0f);
+		glVertex2f(peak_pos + 0.1, 0.0f);
+		glEnd();
+
+		glColor4f(1.0f, 1.0f, 1.0f, 1.0f);
+		glBegin(GL_LINES);
+
+		for (int i = 0; i < 6; ++i) {
+			double pos = find_pos(notes[i].freq);
+			glVertex2f(pos, 0.0f);
+			glVertex2f(pos, 1.0f);
+		}
+		glEnd();
+
+		SDL_GL_SwapBuffers();
+	}
+}