Add music loading/playing using portaudio and stb_vorbis.

.gitmodules

@@ -1,3 +1,6 @@
 [submodule "mach-freetype"]
 	path = mach-freetype
 	url = https://github.com/hexops/mach-freetype
+[submodule "portaudio"]
+	path = portaudio
+	url = git@github.com:PortAudio/portaudio.git

assets/cubyz/biomes/colorado_mountains.json

@@ -0,0 +1,34 @@
+{
+	"type" : "mountain_grassland",
+	"minHeight" : 60,
+	"maxHeight" : 256,
+	
+	"roughness" : 10,
+	"mountains" : 20,
+	"hills" : 50,
+	
+	"rivers" : true,
+	
+	"ground_structure" : [
+	],
+	"stoneBlock" : "cubyz:colorado_stone",
+	"structures" : [
+		{
+			"id" : "cubyz:simple_tree",
+			"leaves" : "cubyz:colorado_stone",
+			"log" : "cubyz:colorado_stone",
+			"top" : "cubyz:colorado_stone",
+			"chance" : 0.001,
+			"type" : "round",
+			"height" : 3,
+			"height_variation" : 1
+		},
+		{
+			"id" : "cubyz:boulder",
+			"chance" : 0.001,
+			"block" : "cubyz:colorado_stone",
+			"size" : 2,
+			"size_variance" : 7
+		}
+	]
+}

assets/cubyz/blocks/colorado_stone.json

@@ -0,0 +1,10 @@
+{
+	"class" : "stone",
+	"hardness" : 20,
+	"breakingPower" : 1,
+	"drops" : [
+		"auto"
+	],
+	"model" : "cube",
+	"texture" : "cubyz:colorado_stone"
+}

assets/cubyz/music/credits.txt

@@ -0,0 +1,37 @@
+TotalDemented ( https://www.youtube.com/channel/UCut9PCEq4cEJogfEPUXk7Gg ):
+cubyz.ogg
+leaves.ogg
+in_the_depths.ogg
+
+
+sinanimea:
+sunrise.ogg
+under_the_water_sky.ogg
+
+
+
+Kevin MacLeod
+
+Syncerely by Kevin MacLeod
+Link: https://incompetech.filmmusic.io/song/5033-sincerely
+License: https://filmmusic.io/standard-license
+
+Gymnopedie No. 1 by Kevin MacLeod
+Link: https://incompetech.filmmusic.io/song/3837-gymnopedie-no-1
+License: https://filmmusic.io/standard-license
+
+Dark Times by Kevin MacLeod
+Link: https://incompetech.filmmusic.io/song/3611-dark-times
+License: https://filmmusic.io/standard-license
+
+Eastern Thought by Kevin MacLeod
+Link: https://incompetech.filmmusic.io/song/3692-eastern-thought
+License: https://filmmusic.io/standard-license
+
+Mana Two Part 2 by Kevin MacLeod
+Link: https://incompetech.filmmusic.io/song/5713-mana-two-part-2
+License: https://filmmusic.io/standard-license
+
+Heart of the Beast by Kevin MacLeod
+Link: https://incompetech.filmmusic.io/song/3862-heart-of-the-beast
+License: https://filmmusic.io/standard-license

build.zig

@@ -43,7 +43,35 @@ pub fn build(b: *std.build.Builder) !void {
 			std.log.err("Unsupported target: {}\n", .{ target.getOsTag() });
 		}
 	}
-	exe.addCSourceFiles(&[_][]const u8{"lib/glad.c", "lib/stb_image.c", "lib/stb_image_write.c"}, &[_][]const u8{"-g", "-O3"});
+	{ // compile portaudio from source:
+		exe.addIncludePath("portaudio/include");
+		exe.addIncludePath("portaudio/src/common");
+		exe.addCSourceFiles(&[_][]const u8 {
+		    "portaudio/src/common/pa_allocation.c",
+			"portaudio/src/common/pa_converters.c",
+			"portaudio/src/common/pa_cpuload.c",
+			"portaudio/src/common/pa_debugprint.c",
+			"portaudio/src/common/pa_dither.c",
+			"portaudio/src/common/pa_front.c",
+			"portaudio/src/common/pa_process.c",
+			"portaudio/src/common/pa_ringbuffer.c",
+			"portaudio/src/common/pa_stream.c",
+			"portaudio/src/common/pa_trace.c",
+		}, &[_][]const u8{"-g", "-O3"});
+		if(target.getOsTag() == .windows) {
+			// TODO: Choose a host API
+		} else if(target.getOsTag() == .linux) {
+			// unix:
+			exe.addCSourceFiles(&[_][]const u8 {"portaudio/src/os/unix/pa_unix_hostapis.c", "portaudio/src/os/unix/pa_unix_util.c"}, &[_][]const u8{"-g", "-O3", "-DPA_USE_ALSA"});
+			exe.addIncludePath("portaudio/src/os/unix");
+			// ALSA:
+			exe.addCSourceFiles(&[_][]const u8 {"portaudio/src/hostapi/alsa/pa_linux_alsa.c"}, &[_][]const u8{"-g", "-O3"});
+			exe.linkSystemLibrary("alsa");
+		} else {
+			std.log.err("Unsupported target: {}\n", .{ target.getOsTag() });
+		}
+	}
+	exe.addCSourceFiles(&[_][]const u8{"lib/glad.c", "lib/stb_image.c", "lib/stb_image_write.c", "lib/stb_vorbis.c"}, &[_][]const u8{"-g", "-O3"});
 	exe.addAnonymousModule("gui", .{.source_file = .{.path = "src/gui/gui.zig"}});
 	exe.addAnonymousModule("server", .{.source_file = .{.path = "src/server/server.zig"}});
 	const harfbuzzModule = freetype.harfbuzzModule(b);

lib/stb_vorbis.c

@@ -0,0 +1,3 @@
+#define STB_VORBIS_NO_PUSHDATA_API
+#define STB_VORBIS_NO_INTEGER_CONVERSION
+#include "stb/stb_vorbis.h"

portaudio

@@ -0,0 +1 @@
+Subproject commit cb8d3dcbc6fa74c67f3e236be89b12d5630da141

src/audio.zig

@@ -0,0 +1,91 @@
+const std = @import("std");
+
+const main = @import("root");
+
+const c = @cImport ({
+	@cInclude("portaudio.h");
+	@cDefine("STB_VORBIS_HEADER_ONLY", "");
+	@cInclude("stb/stb_vorbis.h");
+});
+
+fn handleError(paError: c_int) void {
+	if(paError != c.paNoError) {
+		std.log.err("PortAudio error: {s}", .{c.Pa_GetErrorText(paError)});
+		@panic("Audio error");
+	}
+}
+
+// TODO: Proper sound and music system
+// TODO: volume control
+
+var stream: ?*c.PaStream = null;
+
+var musicData: []f32 = undefined; // TODO: Add a caching system for music data.
+
+const sampleRate = 44100;
+
+pub fn init() !void {
+	handleError(c.Pa_Initialize());
+
+	handleError(c.Pa_OpenDefaultStream(
+		&stream,
+		0, // input channels
+		2, // stereo output
+		c.paFloat32,
+		sampleRate, // TODO: There must be some target dependant value to put here.
+		c.paFramesPerBufferUnspecified,
+		&patestCallback,
+		null
+	));
+
+	var err: c_int = 0;
+	const ogg_stream = c.stb_vorbis_open_filename("assets/cubyz/music/cubyz.ogg", &err, null);
+	defer c.stb_vorbis_close(ogg_stream);
+	if(ogg_stream != null) {
+		const ogg_info: c.stb_vorbis_info = c.stb_vorbis_get_info(ogg_stream);
+		std.debug.assert(sampleRate == ogg_info.sample_rate); // TODO: Handle this case
+		std.debug.assert(2 == ogg_info.channels); // TODO: Handle this case
+		const samples = c.stb_vorbis_stream_length_in_samples(ogg_stream);
+		musicData = try main.globalAllocator.alloc(f32, samples*@intCast(usize, ogg_info.channels));
+		_ = c.stb_vorbis_get_samples_float_interleaved(ogg_stream, ogg_info.channels, musicData.ptr, @intCast(c_int, samples)*ogg_info.channels);
+	} else {
+		std.log.err("Error reading file TODO", .{});
+	}
+
+	handleError(c.Pa_StartStream(stream));
+}
+
+pub fn deinit() void {
+	handleError(c.Pa_StopStream(stream));
+	handleError(c.Pa_CloseStream(stream));
+	handleError(c.Pa_Terminate());
+	main.globalAllocator.free(musicData);
+}
+
+var curIndex: usize = 0;
+
+fn patestCallback(
+	inputBuffer: ?*const anyopaque,
+	outputBuffer: ?*anyopaque,
+	framesPerBuffer: c_ulong,
+	timeInfo: ?*const c.PaStreamCallbackTimeInfo,
+	statusFlags: c.PaStreamCallbackFlags,
+	userData: ?*anyopaque
+) callconv(.C) c_int {
+	// This routine will be called by the PortAudio engine when audio is needed.
+	// It may called at interrupt level on some machines so don't do anything
+	// that could mess up the system like calling malloc() or free().
+	_ = inputBuffer;
+	_ = timeInfo; // TODO: Synchronize this to the rest of the world
+	_ = statusFlags;
+	_ = userData;
+	const out = @ptrCast([*]f32, @alignCast(4, outputBuffer));
+	for(0..framesPerBuffer) |i| {
+		out[2*i] = musicData[curIndex];
+		out[2*i+1] = musicData[curIndex+1];
+		curIndex = (curIndex + 2)%musicData.len;
+	}
+	return 0;
+}
+
+

src/main.zig

@@ -3,6 +3,7 @@ const std = @import("std");
 pub const gui = @import("gui");
 pub const server = @import("server");
 
+pub const audio = @import("audio.zig");
 pub const assets = @import("assets.zig");
 pub const blocks = @import("blocks.zig");
 pub const chunk = @import("chunk.zig");
@@ -511,6 +512,9 @@ pub fn main() !void {
 	try graphics.init();
 	defer graphics.deinit();
 
+	try audio.init();
+	defer audio.deinit();
+
 	try gui.init();
 	defer gui.deinit();