mirror of
https://github.com/ZDoom/raze-gles.git
synced 2024-12-30 13:21:04 +00:00
129 lines
4.3 KiB
C++
129 lines
4.3 KiB
C++
/*
|
|
** Polygon Doom software renderer
|
|
** Copyright (c) 2016 Magnus Norddahl
|
|
**
|
|
** This software is provided 'as-is', without any express or implied
|
|
** warranty. In no event will the authors be held liable for any damages
|
|
** arising from the use of this software.
|
|
**
|
|
** Permission is granted to anyone to use this software for any purpose,
|
|
** including commercial applications, and to alter it and redistribute it
|
|
** freely, subject to the following restrictions:
|
|
**
|
|
** 1. The origin of this software must not be misrepresented; you must not
|
|
** claim that you wrote the original software. If you use this software
|
|
** in a product, an acknowledgment in the product documentation would be
|
|
** appreciated but is not required.
|
|
** 2. Altered source versions must be plainly marked as such, and must not be
|
|
** misrepresented as being the original software.
|
|
** 3. This notice may not be removed or altered from any source distribution.
|
|
**
|
|
*/
|
|
|
|
#pragma once
|
|
|
|
#include <cstdint>
|
|
#include <vector>
|
|
#include <float.h>
|
|
#include "renderstyle.h"
|
|
//#include "rendering/swrenderer/drawers/r_draw.h"
|
|
|
|
class FString;
|
|
class PolyTriangleThreadData;
|
|
|
|
struct ScreenTriVertex
|
|
{
|
|
float x, y, z, w;
|
|
float u, v;
|
|
float worldX, worldY, worldZ;
|
|
float a, r, g, b;
|
|
float gradientdistZ;
|
|
};
|
|
|
|
struct ScreenTriangleStepVariables
|
|
{
|
|
float W, U, V;
|
|
float WorldX, WorldY, WorldZ;
|
|
float A, R, G, B;
|
|
float GradientdistZ;
|
|
};
|
|
|
|
struct TriDrawTriangleArgs
|
|
{
|
|
ScreenTriVertex *v1;
|
|
ScreenTriVertex *v2;
|
|
ScreenTriVertex *v3;
|
|
ScreenTriangleStepVariables gradientX;
|
|
ScreenTriangleStepVariables gradientY;
|
|
|
|
bool CalculateGradients()
|
|
{
|
|
float bottomX = (v2->x - v3->x) * (v1->y - v3->y) - (v1->x - v3->x) * (v2->y - v3->y);
|
|
float bottomY = (v1->x - v3->x) * (v2->y - v3->y) - (v2->x - v3->x) * (v1->y - v3->y);
|
|
if ((bottomX >= -FLT_EPSILON && bottomX <= FLT_EPSILON) || (bottomY >= -FLT_EPSILON && bottomY <= FLT_EPSILON))
|
|
return false;
|
|
|
|
gradientX.W = FindGradientX(bottomX, 1.0f, 1.0f, 1.0f);
|
|
gradientX.U = FindGradientX(bottomX, v1->u, v2->u, v3->u);
|
|
gradientX.V = FindGradientX(bottomX, v1->v, v2->v, v3->v);
|
|
gradientX.WorldX = FindGradientX(bottomX, v1->worldX, v2->worldX, v3->worldX);
|
|
gradientX.WorldY = FindGradientX(bottomX, v1->worldY, v2->worldY, v3->worldY);
|
|
gradientX.WorldZ = FindGradientX(bottomX, v1->worldZ, v2->worldZ, v3->worldZ);
|
|
gradientX.A = FindGradientX(bottomX, v1->a, v2->a, v3->a);
|
|
gradientX.R = FindGradientX(bottomX, v1->r, v2->r, v3->r);
|
|
gradientX.G = FindGradientX(bottomX, v1->g, v2->g, v3->g);
|
|
gradientX.B = FindGradientX(bottomX, v1->b, v2->b, v3->b);
|
|
gradientX.GradientdistZ = FindGradientX(bottomX, v1->gradientdistZ, v2->gradientdistZ, v3->gradientdistZ);
|
|
|
|
gradientY.W = FindGradientY(bottomY, 1.0f, 1.0f, 1.0f);
|
|
gradientY.U = FindGradientY(bottomY, v1->u, v2->u, v3->u);
|
|
gradientY.V = FindGradientY(bottomY, v1->v, v2->v, v3->v);
|
|
gradientY.WorldX = FindGradientY(bottomY, v1->worldX, v2->worldX, v3->worldX);
|
|
gradientY.WorldY = FindGradientY(bottomY, v1->worldY, v2->worldY, v3->worldY);
|
|
gradientY.WorldZ = FindGradientY(bottomY, v1->worldZ, v2->worldZ, v3->worldZ);
|
|
gradientY.A = FindGradientY(bottomY, v1->a, v2->a, v3->a);
|
|
gradientY.R = FindGradientY(bottomY, v1->r, v2->r, v3->r);
|
|
gradientY.G = FindGradientY(bottomY, v1->g, v2->g, v3->g);
|
|
gradientY.B = FindGradientY(bottomY, v1->b, v2->b, v3->b);
|
|
gradientY.GradientdistZ = FindGradientY(bottomY, v1->gradientdistZ, v2->gradientdistZ, v3->gradientdistZ);
|
|
|
|
return true;
|
|
}
|
|
|
|
private:
|
|
float FindGradientX(float bottomX, float c0, float c1, float c2)
|
|
{
|
|
c0 *= v1->w;
|
|
c1 *= v2->w;
|
|
c2 *= v3->w;
|
|
return ((c1 - c2) * (v1->y - v3->y) - (c0 - c2) * (v2->y - v3->y)) / bottomX;
|
|
}
|
|
|
|
float FindGradientY(float bottomY, float c0, float c1, float c2)
|
|
{
|
|
c0 *= v1->w;
|
|
c1 *= v2->w;
|
|
c2 *= v3->w;
|
|
return ((c1 - c2) * (v1->x - v3->x) - (c0 - c2) * (v2->x - v3->x)) / bottomY;
|
|
}
|
|
};
|
|
|
|
class ScreenTriangle
|
|
{
|
|
public:
|
|
static void Draw(const TriDrawTriangleArgs* args, PolyTriangleThreadData* thread);
|
|
|
|
private:
|
|
static void(*TestSpanOpts[])(int y, int x0, int x1, const TriDrawTriangleArgs* args, PolyTriangleThreadData* thread);
|
|
};
|
|
|
|
enum SWTestSpan
|
|
{
|
|
SWTRI_DepthTest = 1,
|
|
SWTRI_StencilTest = 2
|
|
};
|
|
|
|
struct TestSpanOpt0 { static const int Flags = 0; };
|
|
struct TestSpanOpt1 { static const int Flags = 1; };
|
|
struct TestSpanOpt2 { static const int Flags = 2; };
|
|
struct TestSpanOpt3 { static const int Flags = 3; };
|