|
// Playing around with SDL + TTF.
//
// Based on `hello_sdl.c`, zig + SDL code from https://github.com/andrewrk/sdl-zig-demo.
//
// Resources:
// - http://wiki.libsdl.org/CategoryAPI
// - https://www.libsdl.org/projects/SDL_ttf/docs/SDL_ttf.html
//
// Unrelatedly, https://ziglang.org/learn/samples/ lead me to
// raylib, which looks like a really neat library to get started with
// game programming without Godot or Unity:
// https://github.com/raysan5/raylib
const c = @cImport({
@cInclude("SDL2/SDL.h");
@cInclude("SDL2/SDL_ttf.h");
});
const std = @import("std");
pub fn main() !void {
var general_purpose_allocator = std.heap.GeneralPurposeAllocator(.{}){};
const gpa = &general_purpose_allocator.allocator;
const args = try std.process.argsAlloc(gpa);
defer std.process.argsFree(gpa, args);
if (c.SDL_Init(c.SDL_INIT_VIDEO) != 0) {
c.SDL_Log("Unable to initialize SDL: %s", c.SDL_GetError());
return error.SDLInitializationFailed;
}
defer c.SDL_Quit();
if (c.TTF_Init() != 0) {
c.SDL_Log("Unable to initialize SDL_ttf: %s", c.TTF_GetError());
return error.TTFInitializationFailed;
}
defer c.TTF_Quit();
var font_file = if (args.len > 1) args[1] else "./FantasqueSansMono-Regular.ttf";
const font = c.TTF_OpenFont(font_file, 16) orelse {
c.SDL_Log("Unable to load font: %s", c.TTF_GetError());
return error.TTFInitializationFailed;
};
defer c.TTF_CloseFont(font);
c.SDL_Log("Using font %s", font_file.ptr);
// assume monospace font
var glyph_width: c_int = 0;
if (c.TTF_GlyphMetrics(font, 'g', null, null, null, null, &glyph_width) != 0) {
c.SDL_Log("Unable to measure glyph: %s", c.TTF_GetError());
return error.TTFInitializationFailed;
}
var glyph_height = c.TTF_FontLineSkip(font);
var window_width = glyph_width * 100;
var window_height = glyph_height * 20;
const screen = c.SDL_CreateWindow("hello fonts", c.SDL_WINDOWPOS_CENTERED, c.SDL_WINDOWPOS_CENTERED, window_width, window_height, c.SDL_WINDOW_BORDERLESS) orelse {
c.SDL_Log("Unable to create window: %s", c.SDL_GetError());
return error.SDLInitializationFailed;
};
defer c.SDL_DestroyWindow(screen);
const renderer = c.SDL_CreateRenderer(screen, -1, c.SDL_RENDERER_ACCELERATED);
var msg = " ".*;
var pos: usize = 0;
var max_chars = std.math.min(@divTrunc(@intCast(usize, window_width), @intCast(usize, glyph_width)), msg.len);
var result: []const u8 = try gpa.alloc(u8, 0);
const keyboardState = c.SDL_GetKeyboardState(null);
c.SDL_StartTextInput();
var quit = false;
var skip: i32 = 0;
while (!quit) {
var event: c.SDL_Event = undefined;
while (c.SDL_PollEvent(&event) != 0) {
const ctrlPressed = (keyboardState[c.SDL_SCANCODE_LCTRL] != 0);
switch (event.@"type") {
c.SDL_QUIT => {
quit = true;
},
c.SDL_WINDOWEVENT => {
switch (event.window.event) {
c.SDL_WINDOWEVENT_SIZE_CHANGED => {
window_width = event.window.data1;
window_height = event.window.data2;
},
else => {},
}
},
c.SDL_KEYDOWN => {
if (ctrlPressed) {
switch (event.key.keysym.sym) {
c.SDLK_a => {
pos = 0;
msg[pos] = '_';
},
c.SDLK_k => {
var i: usize = 0;
while (i < max_chars) : (i += 1) {
msg[i] = ' ';
}
msg[max_chars] = 0;
pos = 0;
},
c.SDLK_c => {
const clipboard_text = try gpa.dupeZ(u8, result);
if (c.SDL_SetClipboardText(clipboard_text) != 0) {
c.SDL_Log("Could not set clipboard text: %s", c.SDL_GetError());
}
gpa.free(clipboard_text);
},
c.SDLK_v => {
const clipboard_text = c.SDL_GetClipboardText();
if (std.mem.len(clipboard_text) == 0) {
c.SDL_Log("Could not get clipboard: %s", c.SDL_GetError());
} else {
const initial_pos = pos;
while (pos < max_chars and pos - initial_pos < std.mem.len(clipboard_text)) : (pos += 1) {
msg[pos] = clipboard_text[pos - initial_pos];
}
msg[pos] = ' ';
msg[max_chars] = 0;
}
c.SDL_free(clipboard_text);
},
else => {},
}
} else {
switch (event.key.keysym.sym) {
c.SDLK_ESCAPE => {
quit = true;
},
c.SDLK_BACKSPACE => {
pos = if (pos == 0) max_chars - 1 else (pos - 1) % (max_chars - 1);
msg[pos] = '_';
},
c.SDLK_RETURN => {
skip = 0;
gpa.free(result);
result = try runCommand(&msg, gpa);
var i: usize = 0;
while (i < max_chars) : (i += 1) {
msg[i] = ' ';
}
msg[max_chars] = 0;
pos = 0;
},
c.SDLK_UP => {
if (skip > 0) {
skip -= 1;
}
},
c.SDLK_PAGEUP => {
if (skip < 10) {
skip = 0;
} else {
skip -= 10;
}
},
c.SDLK_DOWN => {
skip += 1;
},
c.SDLK_PAGEDOWN => {
skip += 10;
},
else => {},
}
}
},
c.SDL_TEXTINPUT => {
if (!ctrlPressed and event.text.text.len > 0) {
c.SDL_Log("input: '%s' at %d", event.text.text, pos);
msg[pos] = event.text.text[0];
pos = (pos + 1) % (max_chars - 1);
}
},
else => {},
}
}
_ = c.SDL_RenderClear(renderer);
// thanks to https://stackoverflow.com/questions/22886500/how-to-render-text-in-sdl2 for some actually useful code here
const white: c.SDL_Color = c.SDL_Color{ .r = 255, .g = 255, .b = 255, .a = 255 };
const black: c.SDL_Color = c.SDL_Color{ .r = 0, .g = 0, .b = 0, .a = 255 };
// Shaded vs Solid gives a nicer output, with solid the output
// was squiggly and not aligned with a baseline.
const text = c.TTF_RenderUTF8_Shaded(font, &msg, white, black);
const texture = c.SDL_CreateTextureFromSurface(renderer, text);
c.SDL_FreeSurface(text);
_ = c.SDL_RenderCopy(renderer, texture, null, &c.SDL_Rect{ .x = 0, .y = 0, .w = @intCast(c_int, msg.len) * glyph_width, .h = glyph_height });
var i: c_int = 1;
var lines = std.mem.split(result, "\n");
var line = lines.next();
{
var skipped: i32 = 0;
while (skipped < skip and line != null) : (skipped += 1) {
line = lines.next();
}
}
while (line != null and i * glyph_height < window_height) {
const line_c = try gpa.dupeZ(u8, line.?);
const result_text = c.TTF_RenderUTF8_Shaded(font, line_c, white, black);
gpa.free(line_c);
const result_texture = c.SDL_CreateTextureFromSurface(renderer, result_text);
_ = c.SDL_RenderCopy(renderer, result_texture, null, &c.SDL_Rect{ .x = 0, .y = i * glyph_height, .w = @intCast(c_int, line.?.len) * glyph_width, .h = glyph_height });
c.SDL_FreeSurface(result_text);
c.SDL_DestroyTexture(result_texture);
i += 1;
line = lines.next();
}
_ = c.SDL_RenderPresent(renderer);
c.SDL_Delay(16);
}
_ = general_purpose_allocator.detectLeaks();
}
fn runCommand(raw_cmd: []const u8, allocator: *std.mem.Allocator) ![]const u8 {
const cmd = std.mem.trim(u8, std.mem.sliceTo(raw_cmd, 0), &std.ascii.spaces);
const argv = if (std.mem.startsWith(u8, cmd, "go "))
&[_][]const u8{ "go", "doc", cmd[3..] }
else if (std.mem.startsWith(u8, cmd, "py "))
&[_][]const u8{ "python", "-c", try std.fmt.allocPrint(allocator, "import {s}; help({s});", .{ std.mem.sliceTo(cmd["py ".len..], '.'), cmd["py ".len..] }) }
else if (std.mem.endsWith(u8, cmd, " --help"))
// TODO: handle --help that outputs on stderr
&[_][]const u8{ cmd[0..(cmd.len - " --help".len)], "--help" }
else if (std.mem.startsWith(u8, cmd, "man "))
// TODO: handle `man 5 sway`
&[_][]const u8{ "man", cmd["man ".len..] }
else if (cmd.len > 0 and std.ascii.isDigit(cmd[0]))
&[_][]const u8{ "/usr/bin/qalc", "-terse", cmd }
else
&[_][]const u8{ "bash", "-c", cmd };
for (argv) |arg| {
std.debug.print("'{s}' ", .{arg});
}
const result = try std.ChildProcess.exec(.{ .allocator = allocator, .argv = argv, .max_output_bytes = 1024 * 1024 });
std.debug.print("stderr: '{s}'\n", .{result.stderr});
defer {
// FIXME: allocator.free(result.stdout);
allocator.free(result.stderr);
}
return result.stdout;
}
// tests
test "trim []const u8" {
const untrimmed: []const u8 = " hey there ";
const trimmed = std.mem.trim(u8, untrimmed, &std.ascii.spaces);
try std.testing.expect(trimmed.len < untrimmed.len);
try std.testing.expect(trimmed.len == 9);
try std.testing.expect(std.mem.eql(u8, trimmed, "hey there"));
}
test "trim [*:0]const u8" {
const untrimmed: [*:0]const u8 = " hey there ";
const to_trim: [*:0]const u8 = " ";
const trimmed = std.mem.trim(u8, std.mem.sliceTo(untrimmed, 0), std.mem.sliceTo(to_trim, 0));
try std.testing.expect(std.mem.len(trimmed) < std.mem.len(untrimmed));
try std.testing.expect(trimmed.len == 9);
try std.testing.expect(std.mem.eql(u8, trimmed, "hey there"));
}
|
