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wired
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Remove friction from velocityProcess

master
Louis Pearson 2022-01-19 23:42:44 -07:00
parent a64b7198a0
commit a06d7fb32b
2 changed files with 31 additions and 33 deletions
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43
src/main.zig
View File

@ -144,7 +144,7 @@ export fn start() void {
.pos = Pos.init(Vec2f{ 100, 80 }),
.control = .{ .controller = .player, .state = .stand },
.sprite = .{ .offset = .{ -4, -8 }, .size = .{ 8, 8 }, .index = 0, .flags = .{ .bpp = .b1 } },
.physics = .{ .friction = Vec2f{ 0.05, 0.01 }, .gravity = Vec2f{ 0, 0.25 } },
.physics = .{ .friction = Vec2f{ 0.15, 0.1 }, .gravity = Vec2f{ 0, 0.25 } },
.controlAnim = ControlAnim{
.anims = playerAnim,
.state = Anim{ .anim = &.{} },
@ -159,7 +159,7 @@ export fn start() void {
var nodes = std.BoundedArray(Pos, 32).init(0) catch showErr("Nodes");
var i: usize = 0;
const divisions = @floatToInt(usize, vec_length(size) / 6);
const divisions = @floatToInt(usize, util.lengthf(size) / 6);
while (i <= divisions) : (i += 1) {
const pos = begin + @splat(2, @intToFloat(f32, i)) * size / @splat(2, @intToFloat(f32, divisions));
nodes.append(Pos.init(pos)) catch showErr("Appending nodes");
@ -338,14 +338,14 @@ fn wireManipulationProcess(_: f32, id: usize, pos: *Pos, control: *Control) void
const nodes = wire.nodes.constSlice();
const begin = nodes[0].pos;
const end = nodes[wire.nodes.len - 1].pos;
var dist = distancef(begin, pos.pos + offset);
var dist = util.distancef(begin, pos.pos + offset);
if (dist < minDistance) {
minDistance = dist;
indicator = .{ .t = .wire, .pos = vec2ftovec2(begin) };
interactWireID = entityID;
which = 0;
}
dist = distancef(end, pos.pos + offset);
dist = util.distancef(end, pos.pos + offset);
if (dist < minDistance) {
minDistance = dist;
indicator = .{ .t = .wire, .pos = vec2ftovec2(end) };
@ -365,33 +365,12 @@ fn wireManipulationProcess(_: f32, id: usize, pos: *Pos, control: *Control) void
}
}
fn distance(a: w4.Vec2, b: w4.Vec2) i32 {
var subbed = a - b;
subbed[0] = std.math.absInt(subbed[0]) catch unreachable;
subbed[1] = std.math.absInt(subbed[1]) catch unreachable;
return @reduce(.Max, subbed);
}
fn distancef(a: Vec2f, b: Vec2f) f32 {
var subbed = @fabs(a - b);
return @reduce(.Max, subbed);
}
fn vec_length(vec: Vec2f) f32 {
var squared = vec * vec;
return @sqrt(@reduce(.Add, squared));
}
fn normalize(vec: Vec2f) Vec2f {
return vec / @splat(2, vec_length(vec));
}
fn wirePhysicsProcess(dt: f32, wire: *Wire) void {
var nodes = wire.nodes.slice();
if (nodes.len == 0) return;
for (nodes) |*node| {
var physics = Physics{ .gravity = Vec2f{ 0, 0.25 }, .friction = Vec2f{ 0.05, 0.05 } };
var physics = Physics{ .gravity = Vec2f{ 0, 0.25 }, .friction = Vec2f{ 0.1, 0.1 } };
velocityProcess(dt, node);
physicsProcess(dt, node, &physics);
collideNode(node);
@ -417,7 +396,7 @@ fn collideNode(node: *Pos) void {
const iPos = vec2ftovec2(node.pos);
const mapPos = @divTrunc(iPos, tileSize);
if (map.isSolid(mapPos)) {
const velNorm = normalize(node.pos - node.last);
const velNorm = util.normalizef(node.pos - node.last);
var collideVec = node.last;
while (!map.isSolid(vec2ftovec2((collideVec + velNorm) / tileSizef))) {
collideVec += velNorm;
@ -438,13 +417,13 @@ fn wireLength(wire: *Wire) f32 {
var length: f32 = 0;
var i: usize = 1;
while (i < nodes.len) : (i += 1) {
length += distancef(nodes[i - 1].pos, nodes[i].pos);
length += util.distancef(nodes[i - 1].pos, nodes[i].pos);
}
return length;
}
fn tension(prevNode: *Pos, node: *Pos) f32 {
var dist = distancef(node.pos, prevNode.pos);
var dist = util.distancef(node.pos, prevNode.pos);
var difference: f32 = 0;
if (dist > 0) {
difference = (@minimum(dist, wireSegmentMaxLength) - dist) / dist;
@ -454,7 +433,7 @@ fn tension(prevNode: *Pos, node: *Pos) f32 {
fn constrainNodes(prevNode: *Pos, node: *Pos) void {
var diff = prevNode.pos - node.pos;
var dist = distancef(node.pos, prevNode.pos);
var dist = util.distancef(node.pos, prevNode.pos);
var difference: f32 = 0;
if (dist > 0) {
difference = (wireSegmentMaxLength - dist) / dist;
@ -584,16 +563,14 @@ fn velocityProcess(_: f32, pos: *Pos) void {
if (pos.pinned) return;
var vel = pos.pos - pos.last;
vel *= @splat(2, @as(f32, 0.9));
vel = @minimum(Vec2f{ 8, 8 }, @maximum(Vec2f{ -8, -8 }, vel));
pos.last = pos.pos;
pos.pos += vel;
}
fn physicsProcess(dt: f32, pos: *Pos, physics: *Physics) void {
fn physicsProcess(_: f32, pos: *Pos, physics: *Physics) void {
if (pos.pinned) return;
_ = dt;
var friction = @splat(2, @as(f32, 1)) - physics.friction;
pos.pos = pos.last + (pos.pos - pos.last) * friction;
pos.pos += physics.gravity;

21
src/util.zig
View File

@ -4,6 +4,27 @@ pub const Vec2f = std.meta.Vector(2, f32);
pub const Vec2 = std.meta.Vector(2, i32);
pub const Cell = Vec2;
pub fn distance(a: Vec2, b: Vec2) i32 {
var subbed = a - b;
subbed[0] = std.math.absInt(subbed[0]) catch unreachable;
subbed[1] = std.math.absInt(subbed[1]) catch unreachable;
return @reduce(.Max, subbed);
}
pub fn distancef(a: Vec2f, b: Vec2f) f32 {
var subbed = @fabs(a - b);
return @reduce(.Max, subbed);
}
pub fn lengthf(vec: Vec2f) f32 {
var squared = vec * vec;
return @sqrt(@reduce(.Add, squared));
}
pub fn normalizef(vec: Vec2f) Vec2f {
return vec / @splat(2, lengthf(vec));
}
pub fn world2cell(vec: Vec2f) Vec2 {
return vec2fToVec2(vec / @splat(2, @as(f32, 8)));
}