// Update is called once per frame
void Update()
{
if (first)
{
//first = false;
HScreenDevice.GetInstance().Draw();
for (int i = 0; i < HScreenDevice.GetInstance().ScreenHeight; i++)
{
for (int j = 0; j < HScreenDevice.GetInstance().ScreenWidth; j++)
{
Color color = new Color();
color.r = HScreenDevice.GetInstance()
.FrameBuff[(i * HScreenDevice.GetInstance().ScreenWidth + j) * 4 + 0] / 255.0f;
color.g = HScreenDevice.GetInstance()
.FrameBuff[(i * HScreenDevice.GetInstance().ScreenWidth + j) * 4 + 1] / 255.0f;
color.b = HScreenDevice.GetInstance()
.FrameBuff[(i * HScreenDevice.GetInstance().ScreenWidth + j) * 4 + 2] / 255.0f;
color.a = 255 / 255.0f;
MainTexture.SetPixel(i, j, color);
}
}
MainTexture.Apply();
MainImage.sprite = Sprite.Create(MainTexture, new Rect(0, 0, MainTexture.width, MainTexture.height), new Vector2(0.5f, 0.5f));
}
}
public static HScreenDevice GetInstance()
{
if (DeviceInstance == null)
{
DeviceInstance = new HScreenDevice();
}
return(DeviceInstance);
}
//归一化 且屏幕坐标
//宽->
//高↓
public HVector HomogenizeToScreenCoord(HVector Origin)
{
int ScreenWidth = HScreenDevice.GetInstance().ScreenWidth;
int ScreenHeight = HScreenDevice.GetInstance().ScreenHeight;
float rhw = 1.0f / Origin.w;
HVector vecRet = new HVector();
vecRet.x = (Origin.x * rhw + 1.0f) * ScreenWidth * 0.5f;
vecRet.y = (1.0f - Origin.y * rhw) * ScreenHeight * 0.5f;
vecRet.z = Origin.z * rhw;
vecRet.w = 1.0f;
return(vecRet);
}
// Use this for initialization
void Start()
{
//获取设备宽高 然后初始化
int X = 700;
int Y = 700;
HScreenDevice.GetInstance().Init(X, Y);
//MainTexture
MainTexture = new Texture2D(X, Y, TextureFormat.RGBA32, false);
//设置绘制一个Cube
HScreenDevice.GetInstance().shape = new HCube();
}
public void Init()
{
int ScreenWidth = HScreenDevice.GetInstance().ScreenWidth;
int ScreenHeight = HScreenDevice.GetInstance().ScreenHeight;
ModleMat = MathHelper.GetIdentityMat();
HVector camera = new HVector(5, 0, 0, 1);
HVector at = new HVector(0, 0, 0, 1);
HVector up = new HVector(0, 1, 0, 1);
ViewMat = MathHelper.GetLookAtMat(
camera,
at,
up
);
// fov = 90度 0.5pai
ProjectionMat = MathHelper.GetPerspectiveMat(3.1415926f * 0.5f, (float)ScreenWidth / (float)ScreenHeight, 1.0f, 500.0f);
UpdateMVPMat();
}
void DrawScanline(HScanline scanline)
{
HScreenDevice ScreenDevice = HScreenDevice.GetInstance();
List <byte> framebuffer = ScreenDevice.FrameBuff;
List <float> zbuffer = ScreenDevice.DepthBuff;
int x = (int)scanline.x;
int y = (int)scanline.y;
int scanlineWidth = (int)scanline.width;
int ScreenWidth = ScreenDevice.ScreenWidth;
int ScreenHeight = ScreenDevice.ScreenHeight;
for (; scanlineWidth > 0; x++, scanlineWidth--)
{
if (x >= 0 && x < ScreenWidth)
{
float rhw = scanline.v.rhw;
if (rhw >= zbuffer[x + y * ScreenWidth])
{
float w = 1.0f / rhw;
zbuffer[x + y * ScreenWidth] = rhw;
float u = scanline.v.uv.u * w;
float v = scanline.v.uv.v * w;
v2f fragIn = new v2f();
fragIn.uv.u = u;
fragIn.uv.v = v;
int color = frag(fragIn); //片元着色器
byte r = (byte)0x0, g = (byte)0x0, b = (byte)0x0, a = (byte)0x0;
MathHelper.GetRGBAFromInt(color, ref r, ref g, ref b, ref a);
framebuffer[(x + y * ScreenWidth) * 4] = r;
framebuffer[(x + y * ScreenWidth) * 4 + 1] = g;
framebuffer[(x + y * ScreenWidth) * 4 + 2] = b;
framebuffer[(x + y * ScreenWidth) * 4 + 3] = a;
}
}
scanline.v = scanline.v.Add(scanline.step);
if (x >= ScreenWidth)
{
break;
}
}
}
// 主渲染函数
void DrawTrap(HTrapezoid trap)
{
//HScanline scanline;
int j, top, bottom;
top = (int)(trap.top + 0.5f);
bottom = (int)(trap.bottom + 0.5f);
for (j = top; j < bottom; j++)
{
if (j >= 0 && j < HScreenDevice.GetInstance().ScreenHeight) //todo
//插值得到梯形的腰的两个点
{
trap.EdgeInterp((float)j + 0.5f);
//初始化扫描线
HScanline scanline = GetScanline(trap, j);
//绘制扫描线
DrawScanline(scanline);
}
}
}
