robert@493: /*
robert@493:  * render.cpp
robert@493:  *
robert@493:  *  Created on: Oct 24, 2014
robert@493:  *      Author: parallels
robert@493:  */
robert@493: 
robert@493: 
robert@493: #include <Bela.h>
robert@493: #include "game.h"
robert@493: #include <rtdk.h>
robert@493: #include <cmath>
robert@493: #include <cstdlib>
robert@493: #include <time.h>
robert@493: 
robert@493: int gAudioFramesPerMatrixFrame = 2; // Ratio in audio to matrix sample rate
robert@493: 
robert@493: int gInputTank1Angle = 0;		// Inputs for the cannon angles
robert@493: int gInputTank2Angle = 1;
robert@493: int gInputLauncher = 2;			// Input for launcher FSR
robert@493: 
robert@493: int gOutputX = 0;				// Outputs for the scope
robert@493: int gOutputY = 1;
robert@493: int gOutputPlayer1LED = 2;
robert@493: int gOutputPlayer2LED = 3;
robert@493: 
robert@493: int gGameFramesPerSecond = 60;	// How often the physics are updated
robert@493: int gGameFrameInterval;			// ...and in frames
robert@493: int gSamplesUntilNextFrame;		// Counter until next update
robert@493: int gSamplesSinceFinish = 0;	// How long since somebody won?
robert@493: bool gGameShouldRestart = false;// Whether we need to reinitiliase the game
robert@493: 
robert@493: // Counter for overall number of samples that have elapsed
robert@493: unsigned int gSampleCounter = 0;
robert@493: 
robert@493: // 1st-order filter and peak detector for launcher input
robert@493: float gLauncherLastSample = 0;
robert@493: float gLauncherFilterPole = 0.8;
robert@493: float gLauncherPeakValue = 0;
robert@493: float gLauncherPeakFilterPole = 0.999;
robert@493: float gLauncherNoiseThreshold = 0.01;
robert@493: float gLauncherMinimumPeak = 0.1;
robert@493: bool gLauncherTriggered = false;
robert@493: 
robert@493: // Screen update rate; affects buffer size. Actual contents of buffer
robert@493: // may be smaller than this
robert@493: int gScreenWidth = 512;
robert@493: int gScreenHeight = 512;
robert@493: int gScreenFramesPerSecond = 25;
robert@493: 
robert@493: // Double buffer for rendering screen. Each is an interleaved buffer
robert@493: // of XY data.
robert@493: float *gScreenBuffer1, *gScreenBuffer2;
robert@493: float *gScreenBufferWrite, *gScreenBufferRead;
robert@493: int gScreenBufferMaxLength;				// What is the total buffer allocated?
robert@493: int gScreenBufferReadLength;			// How long is the read buffer?
robert@493: int gScreenBufferWriteLength;			// How long is the write (next) buffer?
robert@493: int gScreenBufferReadPointer;			// Where are we in the read buffer now?
robert@493: int gScreenBufferNextUpdateLocation;	// When should we render the next buffer?
robert@493: bool gScreenNextBufferReady;			// Is the next buffer ready to go?
robert@493: 
robert@493: // Auxiliary (low-priority) task for updating the screen
robert@493: AuxiliaryTask gScreenUpdateTask;
robert@493: 
robert@493: // Buffers for music and sound effects
robert@493: extern float *gMusicBuffer;
robert@493: extern int gMusicBufferLength;
robert@493: extern float *gSoundBoomBuffer;
robert@493: extern int gSoundBoomBufferLength;
robert@493: extern float *gSoundHitBuffer;
robert@493: extern int gSoundHitBufferLength;
robert@493: 
robert@493: // Current state for sound and music
robert@493: int gMusicBufferPointer = 0;	  // 0 means start of buffer...
robert@493: int gSoundBoomBufferPointer = -1; // -1 means don't play...
robert@493: int gSoundHitBufferPointer = -1;
robert@493: float gSoundProjectileOscillatorPhase = 0;
robert@493: float gSoundProjectileOscillatorGain = 0.2;
robert@493: float gOscillatorPhaseScaler = 0;
robert@493: 
robert@493: void screen_update();
robert@493: 
robert@493: // setup() is called once before the audio rendering starts.
robert@493: // Use it to perform any initialisation and allocation which is dependent
robert@493: // on the period size or sample rate.
robert@493: //
robert@493: // userData holds an opaque pointer to a data structure that was passed
robert@493: // in from the call to initAudio().
robert@493: //
robert@493: // Return true on success; returning false halts the program.
robert@493: 
robert@493: bool setup(BelaContext *context, void *userData)
robert@493: {
robert@493: 	srandom(time(NULL));
robert@493: 
chris@543: 	// Verify we are running with analog channels enabled
chris@543: 	if(context->analogFrames == 0 || context->analogOutChannels < 4) {
chris@543: 		rt_printf("Error: this example needs least 4 analog output channels\n");
robert@493: 		return false;
robert@493: 	}
robert@493: 
robert@493: 	// Initialise audio variables
robert@493: 	gAudioFramesPerMatrixFrame = context->audioFrames / context->analogFrames;
robert@493: 	gOscillatorPhaseScaler = 2.0 * M_PI / context->audioSampleRate;
robert@493: 
robert@493: 	// Initialise the screen buffers
robert@493: 	gScreenBufferMaxLength = 2 * context->analogSampleRate / gScreenFramesPerSecond;
robert@493: 	gScreenBuffer1 = new float[gScreenBufferMaxLength];
robert@493: 	gScreenBuffer2 = new float[gScreenBufferMaxLength];
robert@493: 	if(gScreenBuffer1 == 0 || gScreenBuffer2 == 0) {
robert@493: 		rt_printf("Error initialising screen buffers\n");
robert@493: 		return false;
robert@493: 	}
robert@493: 
robert@493: 	gScreenBufferRead = gScreenBuffer1;
robert@493: 	gScreenBufferWrite = gScreenBuffer2;
robert@493: 	gScreenBufferReadLength = gScreenBufferWriteLength = 0;
robert@493: 	gScreenBufferReadPointer = 0;
robert@493: 	gScreenBufferNextUpdateLocation = 0;
robert@493: 	gScreenNextBufferReady = false;
robert@493: 
robert@493: 	// Initialise the game
robert@493: 	setupGame(gScreenWidth, gScreenHeight);
robert@493: 	gGameFrameInterval = context->analogSampleRate / gGameFramesPerSecond;
robert@493: 	gSamplesUntilNextFrame = gGameFrameInterval;
robert@493: 
robert@493: 	// Initialise auxiliary tasks
robert@493: 	if((gScreenUpdateTask = Bela_createAuxiliaryTask(&screen_update, 90,
robert@493: 														 "bela-screen-update")) == 0)
robert@493: 		return false;
robert@493: 
robert@493: 	return true;
robert@493: }
robert@493: 
robert@493: // Swap buffers on the screen
robert@493: void swap_buffers()
robert@493: {
robert@493: 	if(gScreenBufferRead == gScreenBuffer1) {
robert@493: 		gScreenBufferRead = gScreenBuffer2;
robert@493: 		gScreenBufferWrite = gScreenBuffer1;
robert@493: 	}
robert@493: 	else {
robert@493: 		gScreenBufferRead = gScreenBuffer1;
robert@493: 		gScreenBufferWrite = gScreenBuffer2;
robert@493: 	}
robert@493: 
robert@493: 	gScreenBufferReadLength = gScreenBufferWriteLength;
robert@493: 	gScreenBufferReadPointer = 0;
robert@493: 
robert@493: 	// Schedule next update for 3/4 of the way through the buffer
robert@493: 	gScreenBufferNextUpdateLocation = gScreenBufferReadLength * 0.75;
robert@493: 	gScreenNextBufferReady = false;
robert@493: }
robert@493: 
robert@493: // render() is called regularly at the highest priority by the audio engine.
robert@493: // Input and output are given from the audio hardware and the other
robert@493: // ADCs and DACs (if available). If only audio is available, numMatrixFrames
robert@493: // will be 0.
robert@493: 
robert@493: void render(BelaContext *context, void *userData)
robert@493: {
robert@493: 	int audioIndex = 0;
robert@493: 
robert@493: 	for(unsigned int n = 0; n < context->analogFrames; n++) {
robert@493: 		for(int k = 0; k < gAudioFramesPerMatrixFrame; k++) {
robert@493: 			// Render music and sound
robert@493: 			float audioSample = 0;
robert@493: 
robert@493: 			// Music plays in a loop
robert@493: 			if(gMusicBuffer != 0 && gMusicBufferPointer >= 0) {
robert@493: 				audioSample += gMusicBuffer[gMusicBufferPointer++];
robert@493: 				if(gMusicBufferPointer >= gMusicBufferLength)
robert@493: 					gMusicBufferPointer = 0;
robert@493: 			}
robert@493: 
robert@493: 			// Sound effect plays until finished, then stops
robert@493: 			if(gSoundBoomBuffer != 0 && gSoundBoomBufferPointer >= 0) {
robert@493: 				audioSample += gSoundBoomBuffer[gSoundBoomBufferPointer++];
robert@493: 				if(gSoundBoomBufferPointer >= gSoundBoomBufferLength)
robert@493: 					gSoundBoomBufferPointer = -1;
robert@493: 			}
robert@493: 
robert@493: 			if(gSoundHitBuffer != 0 && gSoundHitBufferPointer >= 0) {
robert@493: 				audioSample += gSoundHitBuffer[gSoundHitBufferPointer++];
robert@493: 				if(gSoundHitBufferPointer >= gSoundHitBufferLength)
robert@493: 					gSoundHitBufferPointer = -1;
robert@493: 			}
robert@493: 
robert@493: 			// Oscillator plays to indicate projectile height
robert@493: 			if(gameStatusProjectileInMotion()) {
robert@493: 				audioSample += gSoundProjectileOscillatorGain * sinf(gSoundProjectileOscillatorPhase);
robert@493: 
robert@493: 				gSoundProjectileOscillatorPhase += gOscillatorPhaseScaler * constrain(map(gameStatusProjectileHeight(),
robert@493: 						1.0, 0, 300, 2000), 200, 6000);
robert@493: 				if(gSoundProjectileOscillatorPhase > 2.0 * M_PI)
robert@493: 					gSoundProjectileOscillatorPhase -= 2.0 * M_PI;
robert@493: 			}
robert@493: 
robert@493: 			context->audioOut[2*audioIndex] = context->audioOut[2*audioIndex + 1] = audioSample;
robert@493: 			audioIndex++;
robert@493: 		}
robert@493: 
robert@493: 		// First-order lowpass filter to remove noise on launch FSR
robert@493: 		float rawSample = analogRead(context, n, gInputLauncher);
robert@493: 		float launchSample = gLauncherFilterPole * gLauncherLastSample +
robert@493: 							(1.0f - gLauncherFilterPole) * rawSample;
robert@493: 		gLauncherLastSample = launchSample;
robert@493: 
robert@493: 		// Peak-detect on launch signal
robert@493: 		if(launchSample >= gLauncherPeakValue) {
robert@493: 			gLauncherPeakValue = launchSample;
robert@493: 			gLauncherTriggered = false;
robert@493: 		}
robert@493: 		else {
robert@493: 			if(gLauncherPeakValue - launchSample > gLauncherNoiseThreshold && !gLauncherTriggered) {
robert@493: 				// Detected a peak; is it big enough overall?
robert@493: 				if(gLauncherPeakValue >= gLauncherMinimumPeak) {
robert@493: 					gLauncherTriggered = true;
robert@493: 					// Peak detected-- fire!!
robert@493: 					// Set both cannon strengths but only one will
robert@493: 					// fire depending on whose turn it is
robert@493: 					float strength = map(gLauncherPeakValue,
robert@493: 									     gLauncherMinimumPeak, 1.0,
robert@493: 										 0.5f, 10.0f);
robert@493: 					setTank1CannonStrength(strength);
robert@493: 					setTank2CannonStrength(strength);
robert@493: 					fireProjectile();
robert@493: 				}
robert@493: 			}
robert@493: 
robert@493: 			gLauncherPeakValue *= gLauncherPeakFilterPole;
robert@493: 		}
robert@493: 
robert@493: 		if(--gSamplesUntilNextFrame <= 0) {
robert@493: 			// Update game physics and cannon angles
robert@493: 			gSamplesUntilNextFrame = gGameFrameInterval;
robert@493: 
robert@493: 			setTank1CannonAngle(map(analogRead(context, n, gInputTank1Angle),
robert@493: 									0, 1.0, M_PI, 0));
robert@493: 			setTank2CannonAngle(map(analogRead(context, n, gInputTank2Angle),
robert@493: 									0, 1.0, M_PI, 0));
robert@493: 			nextGameFrame();
robert@493: 
robert@493: 			// Check for collision and start sound accordingly
robert@493: 			if(gameStatusCollisionOccurred()) {
robert@493: 				gSoundBoomBufferPointer = 0;
robert@493: 			}
robert@493: 			
robert@493: 			if(gameStatusTankHitOccurred()) {
robert@493: 				gSoundHitBufferPointer = 0;
robert@493: 			}
robert@493: 		}
robert@493: 
robert@493: 		if(gScreenBufferReadPointer >= gScreenBufferReadLength - 1
robert@493: 			&& gScreenNextBufferReady) {
robert@493: 			// Got to the end; swap buffers
robert@493: 			swap_buffers();
robert@493: 		}
robert@493: 
robert@493: 		// Push current screen buffer to the matrix output
robert@493: 		if(gScreenBufferReadPointer < gScreenBufferReadLength - 1) {
robert@493: 			float x = gScreenBufferRead[gScreenBufferReadPointer++];
robert@493: 			float y = gScreenBufferRead[gScreenBufferReadPointer++];
robert@493: 
robert@493: 			// Rescale screen coordinates to matrix ranges; invert the Y
robert@493: 			// coordinate to go from normal screen coordinates to scope coordinates
robert@493: 			analogWriteOnce(context, n, gOutputX, constrain(map(x, 0, gScreenWidth, 0, 1.0), 0, 1.0));
robert@493: 			analogWriteOnce(context, n, gOutputY, constrain(map(y, 0, gScreenHeight, 1.0, 0), 0, 1.0));
robert@493: 		}
robert@493: 		else {
robert@493: 			// Still not ready! Write 0 until something happens
robert@493: 			analogWriteOnce(context, n, gOutputX, 0);
robert@493: 			analogWriteOnce(context, n, gOutputY, 0);
robert@493: 		}
robert@493: 
robert@493: 		if(gameStatusWinner() != 0) {
robert@493: 			// Blink one LED to show who won
robert@493: 			// Blink both LEDs when projectile is in motion
robert@493: 			float val = (gSampleCounter % 4000 > 2000) ? 1.0 : 0;
robert@493: 			analogWriteOnce(context, n, gOutputPlayer1LED, gameStatusWinner() == 1 ? val : 0);
robert@493: 			analogWriteOnce(context, n, gOutputPlayer2LED, gameStatusWinner() == 2 ? val : 0);
robert@493: 
robert@493: 			// After 5 seconds, restart the game
robert@493: 			gSamplesSinceFinish++;
robert@493: 			if(gSamplesSinceFinish > 22050*5)
robert@493: 				gGameShouldRestart = true;
robert@493: 		}
robert@493: 		else if(gameStatusProjectileInMotion()) {
robert@493: 			// Blink both LEDs when projectile is in motion
robert@493: 			float val = (gSampleCounter % 2000 > 1000) ? 1.0 : 0;
robert@493: 			analogWriteOnce(context, n, gOutputPlayer1LED, val);
robert@493: 			analogWriteOnce(context, n, gOutputPlayer2LED, val);
robert@493: 		}
robert@493: 		else if(gameStatusPlayer1Turn()) {
robert@493: 			analogWriteOnce(context, n, gOutputPlayer1LED, 1.0);
robert@493: 			analogWriteOnce(context, n, gOutputPlayer2LED, 0);
robert@493: 		}
robert@493: 		else {
robert@493: 			analogWriteOnce(context, n, gOutputPlayer2LED, 1.0);
robert@493: 			analogWriteOnce(context, n, gOutputPlayer1LED, 0);
robert@493: 		}
robert@493: 
robert@493: 		// Check if we have reached the point where we should next update
robert@493: 		if(gScreenBufferReadPointer >= gScreenBufferNextUpdateLocation &&
robert@493: 		   !gScreenNextBufferReady) {
robert@493: 			// Update the screen at lower priority than the audio thread
robert@493: 			Bela_scheduleAuxiliaryTask(gScreenUpdateTask);
robert@493: 		}
robert@493: 
robert@493: 		gSampleCounter++;
robert@493: 	}
robert@493: }
robert@493: 
robert@493: void screen_update()
robert@493: {
robert@493: 	// If we should restart, reinitialise the game
robert@493: 	if(gGameShouldRestart) {
robert@493: 		restartGame();
robert@493: 		gGameShouldRestart = false;
robert@493: 		gSamplesSinceFinish = 0;
robert@493: 	}
robert@493: 
robert@493: 	// Render the game based on the current state
robert@493: 	gScreenBufferWriteLength = drawGame(gScreenBufferWrite, gScreenBufferMaxLength);
robert@493: 
robert@493: 	// Flag it as ready to go
robert@493: 	gScreenNextBufferReady = true;
robert@493: }
robert@493: 
robert@493: // cleanup() is called once at the end, after the audio has stopped.
robert@493: // Release any resources that were allocated in setup().
robert@493: 
robert@493: void cleanup(BelaContext *context, void *userData)
robert@493: {
robert@493: 	// Clean up the game state
robert@493: 	cleanupGame();
robert@493: }