minetest/irrlicht
1
0
Fork 0
mirror of https://github.com/minetest/irrlicht.git synced 2024-11-13 22:10:26 +01:00
Code Issues Projects Releases Wiki Activity
3f13323e60
irrlicht/source/Irrlicht/CTRTextureGouraudNoZ.cpp
cutealien ffd7b63af0 API BREAKER: Replacing defines in irrTypes.h which are conflicting with c++ reserved identifier rules. 
C++ has undefined behavior for identifiers starting with __ or with _ followed by an uppercase letter.
We still have many more (in IrrCompileConfig.h and in all header-guards), will likely replace those later as well.
As a workaround for users which might use irrlicht defines in their code, I've added the header irrLegacyDefines.h
Including that allows to continue using old defines for a while - or make it easier to have code which compiles 
with old and new Irrlicht library versions.


git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/trunk@6251 dfc29bdd-3216-0410-991c-e03cc46cb475
2021-08-27 12:55:10 +00:00

365 lines
11 KiB
C++
Raw Blame History

// Copyright (C) 2002-2012 Nikolaus Gebhardt
// This file is part of the "Irrlicht Engine".
// For conditions of distribution and use, see copyright notice in irrlicht.h
#include "IrrCompileConfig.h"
#include "CTRTextureGouraud.h"
#include "SColor.h"
#ifdef _IRR_COMPILE_WITH_SOFTWARE_
namespace irr
{
namespace video
{
class CTRTextureGouraudNoZ : public CTRTextureGouraud
{
public:
CTRTextureGouraudNoZ()
: CTRTextureGouraud(0)
{
#ifdef _DEBUG
setDebugName("CTRGouraudWireNoZ");
#endif
}
//! draws an indexed triangle list
virtual void drawIndexedTriangleList(S2DVertex* vertices, s32 vertexCount, const u16* indexList, s32 triangleCount) IRR_OVERRIDE
{
const S2DVertex *v1, *v2, *v3;
u16 color;
f32 tmpDiv; // temporary division factor
f32 longest; // saves the longest span
s32 height; // saves height of triangle
u16* targetSurface; // target pointer where to plot pixels
s32 spanEnd; // saves end of spans
f32 leftdeltaxf; // amount of pixels to increase on left side of triangle
f32 rightdeltaxf; // amount of pixels to increase on right side of triangle
s32 leftx, rightx; // position where we are
f32 leftxf, rightxf; // same as above, but as f32 values
s32 span; // current span
u16 *hSpanBegin, *hSpanEnd; // pointer used when plotting pixels
s32 leftR, leftG, leftB, rightR, rightG, rightB; // color values
s32 leftStepR, leftStepG, leftStepB,
rightStepR, rightStepG, rightStepB; // color steps
s32 spanR, spanG, spanB, spanStepR, spanStepG, spanStepB; // color interpolating values while drawing a span.
s32 leftTx, rightTx, leftTy, rightTy; // texture interpolating values
s32 leftTxStep, rightTxStep, leftTyStep, rightTyStep; // texture interpolating values
s32 spanTx, spanTy, spanTxStep, spanTyStep; // values of Texturecoords when drawing a span
core::rect<s32> TriangleRect;
lockedSurface = (u16*)RenderTarget->getData();
lockedTexture = (u16*)Texture->getData();
for (s32 i=0; i<triangleCount; ++i)
{
v1 = &vertices[*indexList];
++indexList;
v2 = &vertices[*indexList];
++indexList;
v3 = &vertices[*indexList];
++indexList;
// back face culling
if (BackFaceCullingEnabled)
{
s32 z = ((v3->Pos.X - v1->Pos.X) * (v3->Pos.Y - v2->Pos.Y)) -
((v3->Pos.Y - v1->Pos.Y) * (v3->Pos.X - v2->Pos.X));
if (z < 0)
continue;
}
//near plane clipping
if (v1->ZValue<0 && v2->ZValue<0 && v3->ZValue<0)
continue;
// sort for width for inscreen clipping
if (v1->Pos.X > v2->Pos.X) swapVertices(&v1, &v2);
if (v1->Pos.X > v3->Pos.X) swapVertices(&v1, &v3);
if (v2->Pos.X > v3->Pos.X) swapVertices(&v2, &v3);
if ((v1->Pos.X - v3->Pos.X) == 0)
continue;
TriangleRect.UpperLeftCorner.X = v1->Pos.X;
TriangleRect.LowerRightCorner.X = v3->Pos.X;
// sort for height for faster drawing.
if (v1->Pos.Y > v2->Pos.Y) swapVertices(&v1, &v2);
if (v1->Pos.Y > v3->Pos.Y) swapVertices(&v1, &v3);
if (v2->Pos.Y > v3->Pos.Y) swapVertices(&v2, &v3);
TriangleRect.UpperLeftCorner.Y = v1->Pos.Y;
TriangleRect.LowerRightCorner.Y = v3->Pos.Y;
if (!TriangleRect.isRectCollided(ViewPortRect))
continue;
// calculate height of triangle
height = v3->Pos.Y - v1->Pos.Y;
if (!height)
continue;
// calculate longest span
longest = (v2->Pos.Y - v1->Pos.Y) / (f32)height * (v3->Pos.X - v1->Pos.X) + (v1->Pos.X - v2->Pos.X);
spanEnd = v2->Pos.Y;
span = v1->Pos.Y;
leftxf = (f32)v1->Pos.X;
rightxf = (f32)v1->Pos.X;
leftR = rightR = video::getRed(v1->Color)<<8;
leftG = rightG = video::getGreen(v1->Color)<<8;
leftB = rightB = video::getBlue(v1->Color)<<8;
leftTx = rightTx = v1->TCoords.X;
leftTy = rightTy = v1->TCoords.Y;
targetSurface = lockedSurface + span * SurfaceWidth;
if (longest < 0.0f)
{
tmpDiv = 1.0f / (f32)(v2->Pos.Y - v1->Pos.Y);
rightdeltaxf = (v2->Pos.X - v1->Pos.X) * tmpDiv;
rightStepR = (s32)(((s32)(video::getRed(v2->Color)<<8) - rightR) * tmpDiv);
rightStepG = (s32)(((s32)(video::getGreen(v2->Color)<<8) - rightG) * tmpDiv);
rightStepB = (s32)(((s32)(video::getBlue(v2->Color)<<8) - rightB) * tmpDiv);
rightTxStep = (s32)((v2->TCoords.X - rightTx) * tmpDiv);
rightTyStep = (s32)((v2->TCoords.Y - rightTy) * tmpDiv);
tmpDiv = 1.0f / (f32)height;
leftdeltaxf = (v3->Pos.X - v1->Pos.X) * tmpDiv;
leftStepR = (s32)(((s32)(video::getRed(v3->Color)<<8) - leftR) * tmpDiv);
leftStepG = (s32)(((s32)(video::getGreen(v3->Color)<<8) - leftG) * tmpDiv);
leftStepB = (s32)(((s32)(video::getBlue(v3->Color)<<8) - leftB) * tmpDiv);
leftTxStep = (s32)((v3->TCoords.X - leftTx) * tmpDiv);
leftTyStep = (s32)((v3->TCoords.Y - leftTy) * tmpDiv);
}
else
{
tmpDiv = 1.0f / (f32)height;
rightdeltaxf = (v3->Pos.X - v1->Pos.X) * tmpDiv;
rightStepR = (s32)(((s32)(video::getRed(v3->Color)<<8) - rightR) * tmpDiv);
rightStepG = (s32)(((s32)(video::getGreen(v3->Color)<<8) - rightG) * tmpDiv);
rightStepB = (s32)(((s32)(video::getBlue(v3->Color)<<8) - rightB) * tmpDiv);
rightTxStep = (s32)((v3->TCoords.X - rightTx) * tmpDiv);
rightTyStep = (s32)((v3->TCoords.Y - rightTy) * tmpDiv);
tmpDiv = 1.0f / (f32)(v2->Pos.Y - v1->Pos.Y);
leftdeltaxf = (v2->Pos.X - v1->Pos.X) * tmpDiv;
leftStepR = (s32)(((s32)(video::getRed(v2->Color)<<8) - leftR) * tmpDiv);
leftStepG = (s32)(((s32)(video::getGreen(v2->Color)<<8) - leftG) * tmpDiv);
leftStepB = (s32)(((s32)(video::getBlue(v2->Color)<<8) - leftB) * tmpDiv);
leftTxStep = (s32)((v2->TCoords.X - leftTx) * tmpDiv);
leftTyStep = (s32)((v2->TCoords.Y - leftTy) * tmpDiv);
}
// do it twice, once for the first half of the triangle,
// end then for the second half.
for (s32 triangleHalf=0; triangleHalf<2; ++triangleHalf)
{
if (spanEnd > ViewPortRect.LowerRightCorner.Y)
spanEnd = ViewPortRect.LowerRightCorner.Y;
// if the span <0, than we can skip these spans,
// and proceed to the next spans which are really on the screen.
if (span < ViewPortRect.UpperLeftCorner.Y)
{
// we'll use leftx as temp variable
if (spanEnd < ViewPortRect.UpperLeftCorner.Y)
{
leftx = spanEnd - span;
span = spanEnd;
}
else
{
leftx = ViewPortRect.UpperLeftCorner.Y - span;
span = ViewPortRect.UpperLeftCorner.Y;
}
leftxf += leftdeltaxf*leftx;
rightxf += rightdeltaxf*leftx;
targetSurface += SurfaceWidth*leftx;
leftR += leftStepR*leftx;
leftG += leftStepG*leftx;
leftB += leftStepB*leftx;
rightR += rightStepR*leftx;
rightG += rightStepG*leftx;
rightB += rightStepB*leftx;
leftTx += leftTxStep*leftx;
leftTy += leftTyStep*leftx;
rightTx += rightTxStep*leftx;
rightTy += rightTyStep*leftx;
}
// the main loop. Go through every span and draw it.
while (span < spanEnd)
{
leftx = (s32)(leftxf);
rightx = (s32)(rightxf + 0.5f);
// perform some clipping
// thanks to a correction by hybrid
// calculations delayed to correctly propagate to textures etc.
s32 tDiffLeft=0, tDiffRight=0;
if (leftx<ViewPortRect.UpperLeftCorner.X)
tDiffLeft=ViewPortRect.UpperLeftCorner.X-leftx;
else
if (leftx>ViewPortRect.LowerRightCorner.X)
tDiffLeft=ViewPortRect.LowerRightCorner.X-leftx;
if (rightx<ViewPortRect.UpperLeftCorner.X)
tDiffRight=ViewPortRect.UpperLeftCorner.X-rightx;
else
if (rightx>ViewPortRect.LowerRightCorner.X)
tDiffRight=ViewPortRect.LowerRightCorner.X-rightx;
// draw the span
if (rightx + tDiffRight - leftx - tDiffLeft)
{
tmpDiv = 1.0f / (f32)(rightx - leftx);
spanStepR = (s32)((rightR - leftR) * tmpDiv);
spanR = leftR+tDiffLeft*spanStepR;
spanStepG = (s32)((rightG - leftG) * tmpDiv);
spanG = leftG+tDiffLeft*spanStepG;
spanStepB = (s32)((rightB - leftB) * tmpDiv);
spanB = leftB+tDiffLeft*spanStepB;
spanTxStep = (s32)((rightTx - leftTx) * tmpDiv);
spanTx = leftTx + tDiffLeft*spanTxStep;
spanTyStep = (s32)((rightTy - leftTy) * tmpDiv);
spanTy = leftTy+tDiffLeft*spanTyStep;
hSpanBegin = targetSurface + leftx+tDiffLeft;
hSpanEnd = targetSurface + rightx+tDiffRight;
while (hSpanBegin < hSpanEnd)
{
color = lockedTexture[((spanTy>>8)&textureYMask) * lockedTextureWidth + ((spanTx>>8)&textureXMask)];
*hSpanBegin = video::RGB16(video::getRed(color) * (spanR>>8) >>2,
video::getGreen(color) * (spanG>>8) >>2,
video::getBlue(color) * (spanB>>8) >>2);
spanR += spanStepR;
spanG += spanStepG;
spanB += spanStepB;
spanTx += spanTxStep;
spanTy += spanTyStep;
++hSpanBegin;
}
}
leftxf += leftdeltaxf;
rightxf += rightdeltaxf;
++span;
targetSurface += SurfaceWidth;
leftR += leftStepR;
leftG += leftStepG;
leftB += leftStepB;
rightR += rightStepR;
rightG += rightStepG;
rightB += rightStepB;
leftTx += leftTxStep;
leftTy += leftTyStep;
rightTx += rightTxStep;
rightTy += rightTyStep;
}
if (triangleHalf>0) // break, we've gout only two halves
break;
// setup variables for second half of the triangle.
if (longest < 0.0f)
{
tmpDiv = 1.0f / (v3->Pos.Y - v2->Pos.Y);
rightdeltaxf = (v3->Pos.X - v2->Pos.X) * tmpDiv;
rightxf = (f32)v2->Pos.X;
rightR = video::getRed(v2->Color)<<8;
rightG = video::getGreen(v2->Color)<<8;
rightB = video::getBlue(v2->Color)<<8;
rightStepR = (s32)(((s32)(video::getRed(v3->Color)<<8) - rightR) * tmpDiv);
rightStepG = (s32)(((s32)(video::getGreen(v3->Color)<<8) - rightG) * tmpDiv);
rightStepB = (s32)(((s32)(video::getBlue(v3->Color)<<8) - rightB) * tmpDiv);
rightTx = v2->TCoords.X;
rightTy = v2->TCoords.Y;
rightTxStep = (s32)((v3->TCoords.X - rightTx) * tmpDiv);
rightTyStep = (s32)((v3->TCoords.Y - rightTy) * tmpDiv);
}
else
{
tmpDiv = 1.0f / (v3->Pos.Y - v2->Pos.Y);
leftdeltaxf = (v3->Pos.X - v2->Pos.X) * tmpDiv;
leftxf = (f32)v2->Pos.X;
leftR = video::getRed(v2->Color)<<8;
leftG = video::getGreen(v2->Color)<<8;
leftB = video::getBlue(v2->Color)<<8;
leftStepR = (s32)(((s32)(video::getRed(v3->Color)<<8) - leftR) * tmpDiv);
leftStepG = (s32)(((s32)(video::getGreen(v3->Color)<<8) - leftG) * tmpDiv);
leftStepB = (s32)(((s32)(video::getBlue(v3->Color)<<8) - leftB) * tmpDiv);
leftTx = v2->TCoords.X;
leftTy = v2->TCoords.Y;
leftTxStep = (s32)((v3->TCoords.X - leftTx) * tmpDiv);
leftTyStep = (s32)((v3->TCoords.Y - leftTy) * tmpDiv);
}
spanEnd = v3->Pos.Y;
}
}
}
};
} // end namespace video
} // end namespace irr
#endif // _IRR_COMPILE_WITH_SOFTWARE_
namespace irr
{
namespace video
{
//! creates a flat triangle renderer
ITriangleRenderer* createTriangleRendererTextureGouraudNoZ()
{
#ifdef _IRR_COMPILE_WITH_SOFTWARE_
return new CTRTextureGouraudNoZ();
#else
return 0;
#endif // _IRR_COMPILE_WITH_SOFTWARE_
}
} // end namespace video
} // end namespace irr
Reference in New Issue View Git Blame Copy Permalink