2016-11-27 14:50:45 +11:00

224 lines
8.4 KiB
C#

// ClassicalSharp copyright 2014-2016 UnknownShadow200 | Licensed under MIT
using System;
using System.Drawing;
using ClassicalSharp.GraphicsAPI;
using OpenTK;
#if ANDROID
using Android.Graphics;
#endif
namespace ClassicalSharp.Entities {
/// <summary> Entity component that draws square and circle shadows beneath entities. </summary>
public unsafe sealed class ShadowComponent {
Game game;
Entity entity;
public ShadowComponent(Game game, Entity entity) {
this.game = game;
this.entity = entity;
}
float radius = 7f;
internal void Draw() {
EntityShadow mode = game.Entities.ShadowMode;
Vector3 Position = entity.Position;
float posX = Position.X, posZ = Position.Z;
int posY = Math.Min((int)Position.Y, game.World.Height - 1);
int index = 0, vb = 0;
radius = 7f * Math.Min(entity.ModelScale, 1) * entity.Model.ShadowScale;
VertexP3fT2fC4b[] verts = null;
int posCount = 0, dataCount = 0;
Vector3I* coords = stackalloc Vector3I[4];
ShadowData* data = stackalloc ShadowData[4];
for (int i = 0; i < 4; i++) {
coords[i] = new Vector3I(int.MinValue);
data[i] = new ShadowData();
}
if (mode == EntityShadow.SnapToBlock) {
vb = game.Graphics.texVb; verts = game.Graphics.texVerts;
if (!GetBlocks(coords, ref posCount, posX, posZ, posY, data, ref dataCount)) return;
float x1 = Utils.Floor(posX), z1 = Utils.Floor(posZ);
DraqSquareShadow(verts, ref index, data[0].Y, 220, x1, z1);
} else {
vb = game.ModelCache.vb; verts = game.ModelCache.vertices;
float x = posX - radius/16f, z = posZ - radius/16f;
if (GetBlocks(coords, ref posCount, x, z, posY, data, ref dataCount) && data[0].A > 0)
DrawCircle(verts, ref index, data, dataCount, x, z);
x = Math.Max(posX - radius/16f, Utils.Floor(posX + radius/16f));
if (GetBlocks(coords, ref posCount, x, z, posY, data, ref dataCount) && data[0].A > 0)
DrawCircle(verts, ref index, data, dataCount, x, z);
z = Math.Max(posZ - radius/16f, Utils.Floor(posZ + radius/16f));
if (GetBlocks(coords, ref posCount, x, z, posY, data, ref dataCount) && data[0].A > 0)
DrawCircle(verts, ref index, data, dataCount, x, z);
x = posX - radius/16f;
if (GetBlocks(coords, ref posCount, x, z, posY, data, ref dataCount) && data[0].A > 0)
DrawCircle(verts, ref index, data, dataCount, x, z);
}
if (index == 0) return;
CheckShadowTexture(game.Graphics);
if (!boundShadowTex) {
game.Graphics.BindTexture(shadowTex);
boundShadowTex = true;
}
game.Graphics.UpdateDynamicIndexedVb(DrawMode.Triangles, vb, verts, index);
}
const byte c = 255; // avoids 'ambiguous match' compile errors.
void DraqSquareShadow(VertexP3fT2fC4b[] verts, ref int index, float y, byte alpha, float x, float z) {
int col = new FastColour(c, c, c, alpha).ToArgb();
TextureRec rec = new TextureRec(63/128f, 63/128f, 1/128f, 1/128f);
verts[index++] = new VertexP3fT2fC4b(x, y, z, rec.U1, rec.V1, col);
verts[index++] = new VertexP3fT2fC4b(x + 1, y, z, rec.U2, rec.V1, col);
verts[index++] = new VertexP3fT2fC4b(x + 1, y, z + 1, rec.U2, rec.V2, col);
verts[index++] = new VertexP3fT2fC4b(x, y, z + 1, rec.U1, rec.V2, col);
}
void DrawCircle(VertexP3fT2fC4b[] verts, ref int index,
ShadowData* data, int dataCount, float x, float z) {
x = Utils.Floor(x); z = Utils.Floor(z);
BlockInfo info = game.BlockInfo;
Vector3 min = info.MinBB[data[0].Block], max = info.MaxBB[data[0].Block];
DrawCoords(verts, ref index, data[0], x + min.X, z + min.Z, x + max.X, z + max.Z);
for (int i = 1; i < dataCount; i++) {
Vector3 nMin = info.MinBB[data[i].Block], nMax = info.MaxBB[data[i].Block];
DrawCoords(verts, ref index, data[i], x + min.X, z + nMin.Z, x + max.X, z + min.Z);
DrawCoords(verts, ref index, data[i], x + min.X, z + max.Z, x + max.X, z + nMax.Z);
DrawCoords(verts, ref index, data[i], x + nMin.X, z + nMin.Z, x + min.X, z + nMax.Z);
DrawCoords(verts, ref index, data[i], x + max.X, z + nMin.Z, x + nMax.X, z + nMax.Z);
min = nMin; max = nMax;
}
}
void DrawCoords(VertexP3fT2fC4b[] verts, ref int index, ShadowData data,
float x1, float z1, float x2, float z2) {
Vector3 cen = entity.Position;
if (lequal(x2, x1) || lequal(z2, z1)) return;
float u1 = (x1 - cen.X) * 16/(radius * 2) + 0.5f;
float v1 = (z1 - cen.Z) * 16/(radius * 2) + 0.5f;
float u2 = (x2 - cen.X) * 16/(radius * 2) + 0.5f;
float v2 = (z2 - cen.Z) * 16/(radius * 2) + 0.5f;
if (u2 <= 0 || v2 <= 0 || u1 >= 1 || v1 >= 1) return;
x1 = Math.Max(x1, cen.X - radius/16f); u1 = Math.Max(u1, 0);
z1 = Math.Max(z1, cen.Z - radius/16f); v1 = Math.Max(v1, 0);
x2 = Math.Min(x2, cen.X + radius/16f); u2 = Math.Min(u2, 1);
z2 = Math.Min(z2, cen.Z + radius/16f); v2 = Math.Min(v2, 1);
int col = new FastColour(c, c, c, data.A).ToArgb();
verts[index++] = new VertexP3fT2fC4b(x1, data.Y, z1, u1, v1, col);
verts[index++] = new VertexP3fT2fC4b(x2, data.Y, z1, u2, v1, col);
verts[index++] = new VertexP3fT2fC4b(x2, data.Y, z2, u2, v2, col);
verts[index++] = new VertexP3fT2fC4b(x1, data.Y, z2, u1, v2, col);
}
bool GetBlocks(Vector3I* coords, ref int posCount, float x, float z,
int posY, ShadowData* data, ref int index) {
int blockX = Utils.Floor(x), blockZ = Utils.Floor(z);
Vector3I p = new Vector3I(blockX, 0, blockZ);
BlockInfo info = game.BlockInfo;
Vector3 Position = entity.Position;
index = 0;
// Check we have not processed this particular block already.
if (Position.Y < 0) return false;
for (int i = 0; i < 4; i++) {
if (coords[i] == p) return false;
data[i] = new ShadowData();
}
coords[posCount] = p; posCount++;
while (posY >= 0 && index < 4) {
byte block = GetShadowBlock(blockX, posY, blockZ);
posY--;
byte draw = info.Draw[block];
if (draw == DrawType.Gas || draw == DrawType.Sprite || info.IsLiquid(block)) continue;
float blockY = posY + 1 + info.MaxBB[block].Y;
if (blockY >= Position.Y + 0.01f) continue;
data[index].Block = block; data[index].Y = blockY;
CalcAlpha(Position.Y, ref data[index]);
index++;
// Check if the casted shadow will continue on further down.
if (info.MinBB[block].X == 0 && info.MaxBB[block].X == 1 &&
info.MinBB[block].Z == 0 && info.MaxBB[block].Z == 1) return true;
}
if (index < 4) {
data[index].Block = (byte)game.World.Env.EdgeBlock; data[index].Y = 0;
CalcAlpha(Position.Y, ref data[index]);
index++;
}
return true;
}
byte GetShadowBlock(int x, int y, int z) {
if (x < 0 || z < 0 || x >= game.World.Width || z >= game.World.Length) {
if (y == game.World.Env.EdgeHeight - 1)
return game.BlockInfo.Draw[game.World.Env.EdgeBlock] == DrawType.Gas ? Block.Air : Block.Bedrock;
if (y == game.World.Env.SidesHeight - 1)
return game.BlockInfo.Draw[game.World.Env.SidesBlock] == DrawType.Gas ? Block.Air : Block.Bedrock;
return Block.Air;
}
return game.World.GetBlock(x, y, z);
}
struct ShadowData {
public byte Block;
public float Y;
public byte A;
}
static void CalcAlpha(float playerY, ref ShadowData data) {
float y = data.Y;
if ((playerY - y) <= 6) {
data.A = (byte)(160 - 160 * (playerY - y) / 6);
data.Y += 1/64f; return;
}
data.A = 0;
if ((playerY - y) <= 16) data.Y += 1/64f;
else if ((playerY - y) <= 32) data.Y += 1/16f;
else if ((playerY - y) <= 96) data.Y += 1/8f;
else data.Y += 1/4f;
}
static bool lequal(float a, float b) {
return a < b || Math.Abs(a - b) < 0.001f;
}
internal static bool boundShadowTex = false;
internal static int shadowTex = -1;
static void CheckShadowTexture(IGraphicsApi gfx) {
if (shadowTex != -1) return;
const int size = 128, half = size / 2;
using (Bitmap bmp = Platform.CreateBmp(size, size))
using (FastBitmap fastBmp = new FastBitmap(bmp, true, false))
{
int inPix = new FastColour(0, 0, 0, 200).ToArgb();
int outPix = new FastColour(0, 0, 0, 0).ToArgb();
for (int y = 0; y < fastBmp.Height; y++) {
int* row = fastBmp.GetRowPtr(y);
for (int x = 0; x < fastBmp.Width; x++) {
double dist = (half - (x + 0.5)) * (half - (x + 0.5)) +
(half - (y + 0.5)) * (half - (y + 0.5));
row[x] = dist < half * half ? inPix : outPix;
}
}
shadowTex = gfx.CreateTexture(fastBmp, true);
}
}
}
}