andrewm@10: /*
andrewm@10:  * render.cpp
andrewm@10:  *
andrewm@10:  *  Created on: Oct 24, 2014
andrewm@10:  *      Author: parallels
andrewm@10:  */
andrewm@10: 
andrewm@10: 
giuliomoro@301: #include <Bela.h>
andrewm@10: #include "game.h"
andrewm@10: #include <rtdk.h>
andrewm@10: #include <cmath>
andrewm@10: #include <cstdlib>
andrewm@10: #include <time.h>
andrewm@10: 
andrewm@22: int gAudioFramesPerMatrixFrame = 2; // Ratio in audio to matrix sample rate
andrewm@22: 
andrewm@10: int gInputTank1Angle = 0;		// Inputs for the cannon angles
andrewm@10: int gInputTank2Angle = 1;
andrewm@10: int gInputLauncher = 2;			// Input for launcher FSR
andrewm@10: 
andrewm@10: int gOutputX = 0;				// Outputs for the scope
andrewm@10: int gOutputY = 1;
andrewm@10: int gOutputPlayer1LED = 2;
andrewm@10: int gOutputPlayer2LED = 3;
andrewm@10: 
andrewm@10: int gGameFramesPerSecond = 60;	// How often the physics are updated
andrewm@10: int gGameFrameInterval;			// ...and in frames
andrewm@10: int gSamplesUntilNextFrame;		// Counter until next update
andrewm@10: int gSamplesSinceFinish = 0;	// How long since somebody won?
andrewm@10: bool gGameShouldRestart = false;// Whether we need to reinitiliase the game
andrewm@10: 
andrewm@10: // Counter for overall number of samples that have elapsed
andrewm@10: unsigned int gSampleCounter = 0;
andrewm@10: 
andrewm@10: // 1st-order filter and peak detector for launcher input
andrewm@10: float gLauncherLastSample = 0;
andrewm@10: float gLauncherFilterPole = 0.8;
andrewm@10: float gLauncherPeakValue = 0;
andrewm@10: float gLauncherPeakFilterPole = 0.999;
andrewm@22: float gLauncherNoiseThreshold = 0.01;
andrewm@22: float gLauncherMinimumPeak = 0.1;
andrewm@10: bool gLauncherTriggered = false;
andrewm@10: 
andrewm@10: // Screen update rate; affects buffer size. Actual contents of buffer
andrewm@10: // may be smaller than this
andrewm@10: int gScreenWidth = 512;
andrewm@10: int gScreenHeight = 512;
andrewm@10: int gScreenFramesPerSecond = 25;
andrewm@10: 
andrewm@10: // Double buffer for rendering screen. Each is an interleaved buffer
andrewm@10: // of XY data.
andrewm@10: float *gScreenBuffer1, *gScreenBuffer2;
andrewm@10: float *gScreenBufferWrite, *gScreenBufferRead;
andrewm@10: int gScreenBufferMaxLength;				// What is the total buffer allocated?
andrewm@10: int gScreenBufferReadLength;			// How long is the read buffer?
andrewm@10: int gScreenBufferWriteLength;			// How long is the write (next) buffer?
andrewm@10: int gScreenBufferReadPointer;			// Where are we in the read buffer now?
andrewm@10: int gScreenBufferNextUpdateLocation;	// When should we render the next buffer?
andrewm@10: bool gScreenNextBufferReady;			// Is the next buffer ready to go?
andrewm@10: 
andrewm@10: // Auxiliary (low-priority) task for updating the screen
andrewm@10: AuxiliaryTask gScreenUpdateTask;
andrewm@10: 
andrewm@22: // Buffers for music and sound effects
andrewm@22: extern float *gMusicBuffer;
andrewm@22: extern int gMusicBufferLength;
andrewm@22: extern float *gSoundBoomBuffer;
andrewm@22: extern int gSoundBoomBufferLength;
andrewm@268: extern float *gSoundHitBuffer;
andrewm@268: extern int gSoundHitBufferLength;
andrewm@22: 
andrewm@22: // Current state for sound and music
andrewm@22: int gMusicBufferPointer = 0;	  // 0 means start of buffer...
andrewm@22: int gSoundBoomBufferPointer = -1; // -1 means don't play...
andrewm@268: int gSoundHitBufferPointer = -1;
andrewm@22: float gSoundProjectileOscillatorPhase = 0;
andrewm@22: float gSoundProjectileOscillatorGain = 0.2;
andrewm@22: float gOscillatorPhaseScaler = 0;
andrewm@22: 
andrewm@10: void screen_update();
andrewm@10: 
andrewm@56: // setup() is called once before the audio rendering starts.
andrewm@10: // Use it to perform any initialisation and allocation which is dependent
andrewm@10: // on the period size or sample rate.
andrewm@10: //
andrewm@10: // userData holds an opaque pointer to a data structure that was passed
andrewm@10: // in from the call to initAudio().
andrewm@10: //
andrewm@10: // Return true on success; returning false halts the program.
andrewm@10: 
giuliomoro@301: bool setup(BelaContext *context, void *userData)
andrewm@10: {
andrewm@10: 	srandom(time(NULL));
andrewm@10: 
andrewm@10: 	// Verify we are running with matrix enabled
andrewm@56: 	if(context->analogFrames == 0 || context->analogChannels < 4) {
andrewm@14: 		rt_printf("Error: this example needs the matrix enabled with at least 4 channels\n");
andrewm@10: 		return false;
andrewm@10: 	}
andrewm@10: 
andrewm@22: 	// Initialise audio variables
andrewm@56: 	gAudioFramesPerMatrixFrame = context->audioFrames / context->analogFrames;
andrewm@56: 	gOscillatorPhaseScaler = 2.0 * M_PI / context->audioSampleRate;
andrewm@22: 
andrewm@10: 	// Initialise the screen buffers
andrewm@56: 	gScreenBufferMaxLength = 2 * context->analogSampleRate / gScreenFramesPerSecond;
andrewm@10: 	gScreenBuffer1 = new float[gScreenBufferMaxLength];
andrewm@10: 	gScreenBuffer2 = new float[gScreenBufferMaxLength];
andrewm@10: 	if(gScreenBuffer1 == 0 || gScreenBuffer2 == 0) {
andrewm@10: 		rt_printf("Error initialising screen buffers\n");
andrewm@10: 		return false;
andrewm@10: 	}
andrewm@10: 
andrewm@10: 	gScreenBufferRead = gScreenBuffer1;
andrewm@10: 	gScreenBufferWrite = gScreenBuffer2;
andrewm@10: 	gScreenBufferReadLength = gScreenBufferWriteLength = 0;
andrewm@10: 	gScreenBufferReadPointer = 0;
andrewm@10: 	gScreenBufferNextUpdateLocation = 0;
andrewm@10: 	gScreenNextBufferReady = false;
andrewm@10: 
andrewm@10: 	// Initialise the game
andrewm@10: 	setupGame(gScreenWidth, gScreenHeight);
andrewm@56: 	gGameFrameInterval = context->analogSampleRate / gGameFramesPerSecond;
andrewm@10: 	gSamplesUntilNextFrame = gGameFrameInterval;
andrewm@10: 
andrewm@10: 	// Initialise auxiliary tasks
giuliomoro@301: 	if((gScreenUpdateTask = Bela_createAuxiliaryTask(&screen_update, 90,
andrewm@303: 														 "bela-screen-update")) == 0)
andrewm@10: 		return false;
andrewm@10: 
andrewm@10: 	return true;
andrewm@10: }
andrewm@10: 
andrewm@10: // Swap buffers on the screen
andrewm@10: void swap_buffers()
andrewm@10: {
andrewm@10: 	if(gScreenBufferRead == gScreenBuffer1) {
andrewm@10: 		gScreenBufferRead = gScreenBuffer2;
andrewm@10: 		gScreenBufferWrite = gScreenBuffer1;
andrewm@10: 	}
andrewm@10: 	else {
andrewm@10: 		gScreenBufferRead = gScreenBuffer1;
andrewm@10: 		gScreenBufferWrite = gScreenBuffer2;
andrewm@10: 	}
andrewm@10: 
andrewm@10: 	gScreenBufferReadLength = gScreenBufferWriteLength;
andrewm@10: 	gScreenBufferReadPointer = 0;
andrewm@10: 
andrewm@10: 	// Schedule next update for 3/4 of the way through the buffer
andrewm@10: 	gScreenBufferNextUpdateLocation = gScreenBufferReadLength * 0.75;
andrewm@10: 	gScreenNextBufferReady = false;
andrewm@10: }
andrewm@10: 
andrewm@10: // render() is called regularly at the highest priority by the audio engine.
andrewm@10: // Input and output are given from the audio hardware and the other
andrewm@10: // ADCs and DACs (if available). If only audio is available, numMatrixFrames
andrewm@10: // will be 0.
andrewm@10: 
giuliomoro@301: void render(BelaContext *context, void *userData)
andrewm@10: {
andrewm@22: 	int audioIndex = 0;
andrewm@22: 
andrewm@56: 	for(unsigned int n = 0; n < context->analogFrames; n++) {
andrewm@22: 		for(int k = 0; k < gAudioFramesPerMatrixFrame; k++) {
andrewm@22: 			// Render music and sound
andrewm@22: 			float audioSample = 0;
andrewm@22: 
andrewm@22: 			// Music plays in a loop
andrewm@22: 			if(gMusicBuffer != 0 && gMusicBufferPointer >= 0) {
andrewm@22: 				audioSample += gMusicBuffer[gMusicBufferPointer++];
andrewm@22: 				if(gMusicBufferPointer >= gMusicBufferLength)
andrewm@22: 					gMusicBufferPointer = 0;
andrewm@22: 			}
andrewm@22: 
andrewm@22: 			// Sound effect plays until finished, then stops
andrewm@22: 			if(gSoundBoomBuffer != 0 && gSoundBoomBufferPointer >= 0) {
andrewm@22: 				audioSample += gSoundBoomBuffer[gSoundBoomBufferPointer++];
andrewm@22: 				if(gSoundBoomBufferPointer >= gSoundBoomBufferLength)
andrewm@22: 					gSoundBoomBufferPointer = -1;
andrewm@22: 			}
andrewm@22: 
andrewm@268: 			if(gSoundHitBuffer != 0 && gSoundHitBufferPointer >= 0) {
andrewm@268: 				audioSample += gSoundHitBuffer[gSoundHitBufferPointer++];
andrewm@268: 				if(gSoundHitBufferPointer >= gSoundHitBufferLength)
andrewm@268: 					gSoundHitBufferPointer = -1;
andrewm@268: 			}
andrewm@268: 
andrewm@22: 			// Oscillator plays to indicate projectile height
andrewm@22: 			if(gameStatusProjectileInMotion()) {
andrewm@22: 				audioSample += gSoundProjectileOscillatorGain * sinf(gSoundProjectileOscillatorPhase);
andrewm@22: 
andrewm@22: 				gSoundProjectileOscillatorPhase += gOscillatorPhaseScaler * constrain(map(gameStatusProjectileHeight(),
andrewm@22: 						1.0, 0, 300, 2000), 200, 6000);
andrewm@22: 				if(gSoundProjectileOscillatorPhase > 2.0 * M_PI)
andrewm@22: 					gSoundProjectileOscillatorPhase -= 2.0 * M_PI;
andrewm@22: 			}
andrewm@22: 
andrewm@56: 			context->audioOut[2*audioIndex] = context->audioOut[2*audioIndex + 1] = audioSample;
andrewm@22: 			audioIndex++;
andrewm@22: 		}
andrewm@22: 
andrewm@10: 		// First-order lowpass filter to remove noise on launch FSR
andrewm@311: 		float rawSample = analogRead(context, n, gInputLauncher);
andrewm@10: 		float launchSample = gLauncherFilterPole * gLauncherLastSample +
andrewm@10: 							(1.0f - gLauncherFilterPole) * rawSample;
andrewm@10: 		gLauncherLastSample = launchSample;
andrewm@10: 
andrewm@10: 		// Peak-detect on launch signal
andrewm@10: 		if(launchSample >= gLauncherPeakValue) {
andrewm@10: 			gLauncherPeakValue = launchSample;
andrewm@10: 			gLauncherTriggered = false;
andrewm@10: 		}
andrewm@10: 		else {
andrewm@10: 			if(gLauncherPeakValue - launchSample > gLauncherNoiseThreshold && !gLauncherTriggered) {
andrewm@10: 				// Detected a peak; is it big enough overall?
andrewm@10: 				if(gLauncherPeakValue >= gLauncherMinimumPeak) {
andrewm@10: 					gLauncherTriggered = true;
andrewm@10: 					// Peak detected-- fire!!
andrewm@10: 					// Set both cannon strengths but only one will
andrewm@10: 					// fire depending on whose turn it is
andrewm@10: 					float strength = map(gLauncherPeakValue,
andrewm@22: 									     gLauncherMinimumPeak, 1.0,
andrewm@10: 										 0.5f, 10.0f);
andrewm@10: 					setTank1CannonStrength(strength);
andrewm@10: 					setTank2CannonStrength(strength);
andrewm@10: 					fireProjectile();
andrewm@10: 				}
andrewm@10: 			}
andrewm@10: 
andrewm@10: 			gLauncherPeakValue *= gLauncherPeakFilterPole;
andrewm@10: 		}
andrewm@10: 
andrewm@10: 		if(--gSamplesUntilNextFrame <= 0) {
andrewm@10: 			// Update game physics and cannon angles
andrewm@10: 			gSamplesUntilNextFrame = gGameFrameInterval;
andrewm@10: 
andrewm@311: 			setTank1CannonAngle(map(analogRead(context, n, gInputTank1Angle),
andrewm@22: 									0, 1.0, M_PI, 0));
andrewm@311: 			setTank2CannonAngle(map(analogRead(context, n, gInputTank2Angle),
andrewm@22: 									0, 1.0, M_PI, 0));
andrewm@10: 			nextGameFrame();
andrewm@22: 
andrewm@22: 			// Check for collision and start sound accordingly
andrewm@22: 			if(gameStatusCollisionOccurred()) {
andrewm@22: 				gSoundBoomBufferPointer = 0;
andrewm@22: 			}
andrewm@268: 			
andrewm@268: 			if(gameStatusTankHitOccurred()) {
andrewm@268: 				gSoundHitBufferPointer = 0;
andrewm@268: 			}
andrewm@10: 		}
andrewm@10: 
andrewm@10: 		if(gScreenBufferReadPointer >= gScreenBufferReadLength - 1
andrewm@10: 			&& gScreenNextBufferReady) {
andrewm@10: 			// Got to the end; swap buffers
andrewm@10: 			swap_buffers();
andrewm@10: 		}
andrewm@10: 
andrewm@10: 		// Push current screen buffer to the matrix output
andrewm@10: 		if(gScreenBufferReadPointer < gScreenBufferReadLength - 1) {
andrewm@10: 			float x = gScreenBufferRead[gScreenBufferReadPointer++];
andrewm@10: 			float y = gScreenBufferRead[gScreenBufferReadPointer++];
andrewm@10: 
andrewm@10: 			// Rescale screen coordinates to matrix ranges; invert the Y
andrewm@10: 			// coordinate to go from normal screen coordinates to scope coordinates
andrewm@311: 			analogWriteOnce(context, n, gOutputX, constrain(map(x, 0, gScreenWidth, 0, 1.0), 0, 1.0));
andrewm@311: 			analogWriteOnce(context, n, gOutputY, constrain(map(y, 0, gScreenHeight, 1.0, 0), 0, 1.0));
andrewm@10: 		}
andrewm@10: 		else {
andrewm@10: 			// Still not ready! Write 0 until something happens
andrewm@311: 			analogWriteOnce(context, n, gOutputX, 0);
andrewm@311: 			analogWriteOnce(context, n, gOutputY, 0);
andrewm@10: 		}
andrewm@10: 
andrewm@10: 		if(gameStatusWinner() != 0) {
andrewm@10: 			// Blink one LED to show who won
andrewm@10: 			// Blink both LEDs when projectile is in motion
andrewm@22: 			float val = (gSampleCounter % 4000 > 2000) ? 1.0 : 0;
andrewm@311: 			analogWriteOnce(context, n, gOutputPlayer1LED, gameStatusWinner() == 1 ? val : 0);
andrewm@311: 			analogWriteOnce(context, n, gOutputPlayer2LED, gameStatusWinner() == 2 ? val : 0);
andrewm@10: 
andrewm@10: 			// After 5 seconds, restart the game
andrewm@10: 			gSamplesSinceFinish++;
andrewm@10: 			if(gSamplesSinceFinish > 22050*5)
andrewm@10: 				gGameShouldRestart = true;
andrewm@10: 		}
andrewm@10: 		else if(gameStatusProjectileInMotion()) {
andrewm@10: 			// Blink both LEDs when projectile is in motion
andrewm@22: 			float val = (gSampleCounter % 2000 > 1000) ? 1.0 : 0;
andrewm@311: 			analogWriteOnce(context, n, gOutputPlayer1LED, val);
andrewm@311: 			analogWriteOnce(context, n, gOutputPlayer2LED, val);
andrewm@10: 		}
andrewm@10: 		else if(gameStatusPlayer1Turn()) {
andrewm@311: 			analogWriteOnce(context, n, gOutputPlayer1LED, 1.0);
andrewm@311: 			analogWriteOnce(context, n, gOutputPlayer2LED, 0);
andrewm@10: 		}
andrewm@10: 		else {
andrewm@311: 			analogWriteOnce(context, n, gOutputPlayer2LED, 1.0);
andrewm@311: 			analogWriteOnce(context, n, gOutputPlayer1LED, 0);
andrewm@10: 		}
andrewm@10: 
andrewm@10: 		// Check if we have reached the point where we should next update
andrewm@10: 		if(gScreenBufferReadPointer >= gScreenBufferNextUpdateLocation &&
andrewm@10: 		   !gScreenNextBufferReady) {
andrewm@10: 			// Update the screen at lower priority than the audio thread
giuliomoro@301: 			Bela_scheduleAuxiliaryTask(gScreenUpdateTask);
andrewm@10: 		}
andrewm@10: 
andrewm@10: 		gSampleCounter++;
andrewm@10: 	}
andrewm@10: }
andrewm@10: 
andrewm@10: void screen_update()
andrewm@10: {
andrewm@10: 	// If we should restart, reinitialise the game
andrewm@10: 	if(gGameShouldRestart) {
andrewm@10: 		restartGame();
andrewm@10: 		gGameShouldRestart = false;
andrewm@10: 		gSamplesSinceFinish = 0;
andrewm@10: 	}
andrewm@10: 
andrewm@10: 	// Render the game based on the current state
andrewm@10: 	gScreenBufferWriteLength = drawGame(gScreenBufferWrite, gScreenBufferMaxLength);
andrewm@10: 
andrewm@10: 	// Flag it as ready to go
andrewm@10: 	gScreenNextBufferReady = true;
andrewm@10: }
andrewm@10: 
andrewm@56: // cleanup() is called once at the end, after the audio has stopped.
andrewm@56: // Release any resources that were allocated in setup().
andrewm@10: 
giuliomoro@301: void cleanup(BelaContext *context, void *userData)
andrewm@10: {
andrewm@10: 	// Clean up the game state
andrewm@10: 	cleanupGame();
andrewm@10: }