Replaced the bicubic interpolation filter with a simple sharpening filter

src/CMakeLists.txt

@@ -1190,7 +1190,6 @@ set (PCH_SOURCES
 	textures/texturemanager.cpp
 	textures/tgatexture.cpp
 	textures/warptexture.cpp
-	textures/bicubic_interpolation.cpp
 	thingdef/olddecorations.cpp
 	thingdef/thingdef.cpp
 	thingdef/thingdef_codeptr.cpp

src/r_draw_rgba.cpp

@@ -103,7 +103,9 @@ CVAR(Bool, r_mipmap, true, CVAR_ARCHIVE | CVAR_GLOBALCONFIG);
 
 /////////////////////////////////////////////////////////////////////////////
 
+#ifndef NO_SSE
 __m128i SampleBgra::samplertable[256 * 2];
+#endif
 
 DrawerCommandQueue *DrawerCommandQueue::Instance()
 {
@@ -113,6 +115,7 @@ DrawerCommandQueue *DrawerCommandQueue::Instance()
 
 DrawerCommandQueue::DrawerCommandQueue()
 {
+#ifndef NO_SSE
 	for (int inv_b = 0; inv_b < 16; inv_b++)
 	{
 		for (int inv_a = 0; inv_a < 16; inv_a++)
@@ -132,6 +135,7 @@ DrawerCommandQueue::DrawerCommandQueue()
 			_mm_store_si128(SampleBgra::samplertable + inv_b * 32 + inv_a * 2 + 1, ainvb_invainvb);
 		}
 	}
+#endif
 }
 
 DrawerCommandQueue::~DrawerCommandQueue()

src/textures/bicubic_interpolation.cpp

@@ -1,107 +0,0 @@
-
-#include "doomtype.h"
-#include "bicubic_interpolation.h"
-
-void BicubicInterpolation::ScaleImage(uint32_t *dest_data, int dest_width, int dest_height, const uint32_t *src_data, int src_width, int src_height)
-{
-	if (dest_width <= 0 || dest_height <= 0 || src_width <= 0 || src_height <= 0)
-		return;
-
-	// Scale factor as a rational number r = n / d
-	int n = dest_width;
-	int d = src_width;
-
-	const unsigned char *src_ptr = (const unsigned char *)src_data;
-	unsigned char *dest_ptr = (unsigned char *)dest_data;
-
-	scale(n, d, src_width, src_width * 4, src_height, src_ptr + 0, dest_width, dest_width * 4, dest_height, dest_ptr + 0);
-	scale(n, d, src_width, src_width * 4, src_height, src_ptr + 1, dest_width, dest_width * 4, dest_height, dest_ptr + 1);
-	scale(n, d, src_width, src_width * 4, src_height, src_ptr + 2, dest_width, dest_width * 4, dest_height, dest_ptr + 2);
-	scale(n, d, src_width, src_width * 4, src_height, src_ptr + 3, dest_width, dest_width * 4, dest_height, dest_ptr + 3);
-}
-
-void BicubicInterpolation::scale(int n, int d, int in_width, int in_pitch, int in_height, const unsigned char *f, int out_width, int out_pitch, int out_height, unsigned char *g)
-{
-	// Implementation of Michael J. Aramini's Efficient Image Magnification by Bicubic Spline Interpolation
-
-	int dimension_size = (out_width > out_height) ? out_width : out_height;
-	L_vector.resize(dimension_size);
-
-	for (int i=0;i<4;i++)
-		c_vector[i].resize(dimension_size);
-	h_vector.resize(in_width);
-
-	int larger_out_dimension;
-	int j, k, l, m, index;
-	int *L = &L_vector[0];
-	float x;
-	float *c[4] = { &c_vector[0][0], &c_vector[1][0], &c_vector[2][0], &c_vector[3][0] };
-	float *h = &h_vector[0];
-
-	larger_out_dimension = (out_width > out_height) ? out_width : out_height;
-
-	for (k = 0; k < larger_out_dimension; k++)
-		L[k] = (k * d) / n;
-
-	for (k = 0; k < n; k++)
-	{
-		x = (float)((k * d) % n) / (float)n;
-		c[0][k] = C0(x);
-		c[1][k] = C1(x);
-		c[2][k] = C2(x);
-		c[3][k] = C3(x);
-	}
-	for (k = n; k < larger_out_dimension; k++)
-		for (l = 0; l < 4; l++)
-			c[l][k] = c[l][k % n];
-
-	for (k = 0; k < out_height; k++)
-	{
-		for (j = 0; j < in_width; j++)
-		{
-			h[j] = 0.0f;
-			for (l = 0; l < 4; l++)
-			{
-				index = L[k] + l - 1;
-				if ((index >= 0) && (index < in_height))
-					h[j] += f[index*in_pitch+j*4] * c[3 - l][k];
-			}
-		}
-		for (m = 0; m < out_width; m++)
-		{
-			x = 0.5f;
-			for (l = 0; l < 4; l++)
-			{
-				index = L[m] + l - 1;
-				if ((index >= 0) && (index < in_width))
-					x += h[index] * c[3 - l][m];
-			}
-			if (x <= 0.0f)
-				g[k*out_pitch+m*4] = 0;
-			else if (x >= 255)
-				g[k*out_pitch+m*4] = 255;
-			else
-				g[k*out_pitch+m*4] = (unsigned char)x;
-		}
-	}
-}
-
-inline float BicubicInterpolation::C0(float t)
-{
-	return -a * t * t * t + a * t * t;
-}
-
-inline float BicubicInterpolation::C1(float t)
-{
-	return -(a + 2.0f) * t * t * t + (2.0f * a + 3.0f) * t * t - a * t;
-}
-
-inline float BicubicInterpolation::C2(float t)
-{
-	return (a + 2.0f) * t * t * t - (a + 3.0f) * t * t + 1.0f;
-}
-
-inline float BicubicInterpolation::C3(float t)
-{
-	return a * t * t * t - 2.0f * a * t * t + a * t;
-}

src/textures/bicubic_interpolation.h

@@ -1,50 +0,0 @@
-/*
-**  Bicubic Image Scaler
-**  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.
-*/
-
-#ifndef __BICUBIC_INTERPOLATION_H__
-#define __BICUBIC_INTERPOLATION_H__
-
-#pragma once
-
-#include <vector>
-
-// Bicubic image scaler
-class BicubicInterpolation
-{
-public:
-	void ScaleImage(uint32_t *dest, int dest_width, int dest_height, const uint32_t *src, int src_width, int src_height);
-
-private:
-	void scale(int n, int d, int in_width, int in_pitch, int in_height, const unsigned char *in_data, int out_width, int out_pitch, int out_height, unsigned char *out_data);
-
-	float a = -0.5f; // a is a spline parameter such that -1 <= a <= 0
-
-	inline float C0(float t);
-	inline float C1(float t);
-	inline float C2(float t);
-	inline float C3(float t);
-
-	std::vector<int> L_vector;
-	std::vector<float> c_vector[4];
-	std::vector<float> h_vector;
-};
-
-#endif

src/textures/texture.cpp

@@ -45,7 +45,6 @@
 #include "v_video.h"
 #include "m_fixed.h"
 #include "textures/textures.h"
-#include "textures/bicubic_interpolation.h"
 #include "v_palette.h"
 
 typedef bool (*CheckFunc)(FileReader & file);
@@ -383,20 +382,123 @@ int FTexture::MipmapLevels() const
 
 void FTexture::GenerateBgraMipmaps()
 {
-	BicubicInterpolation bicubic;
+	struct Color4f
+	{
+		float a, r, g, b;
+		Color4f operator*(const Color4f &v) const { return Color4f{ a * v.a, r * v.r, g * v.g, b * v.b }; }
+		Color4f operator/(const Color4f &v) const { return Color4f{ a / v.a, r / v.r, g / v.g, b / v.b }; }
+		Color4f operator+(const Color4f &v) const { return Color4f{ a + v.a, r + v.r, g + v.g, b + v.b }; }
+		Color4f operator-(const Color4f &v) const { return Color4f{ a - v.a, r - v.r, g - v.g, b - v.b }; }
+		Color4f operator*(float s) const { return Color4f{ a * s, r * s, g * s, b * s }; }
+		Color4f operator/(float s) const { return Color4f{ a / s, r / s, g / s, b / s }; }
+		Color4f operator+(float s) const { return Color4f{ a + s, r + s, g + s, b + s }; }
+		Color4f operator-(float s) const { return Color4f{ a - s, r - s, g - s, b - s }; }
+	};
 
-	uint32_t *src = PixelsBgra.data();
-	uint32_t *dest = src + Width * Height;
 	int levels = MipmapLevels();
+	std::vector<Color4f> image(PixelsBgra.size());
+
+	// Convert to normalized linear colorspace
+	{
+		for (int x = 0; x < Width; x++)
+		{
+			for (int y = 0; y < Height; y++)
+			{
+				uint32_t c8 = PixelsBgra[x * Height + y];
+				Color4f c;
+				c.a = std::pow(APART(c8) * (1.0f / 255.0f), 2.2f);
+				c.r = std::pow(RPART(c8) * (1.0f / 255.0f), 2.2f);
+				c.g = std::pow(GPART(c8) * (1.0f / 255.0f), 2.2f);
+				c.b = std::pow(BPART(c8) * (1.0f / 255.0f), 2.2f);
+				image[x * Height + y] = c;
+			}
+		}
+	}
+
+	// Generate mipmaps
+	{
+		std::vector<Color4f> smoothed(Width * Height);
+		Color4f *src = image.data();
+		Color4f *dest = src + Width * Height;
+		for (int i = 1; i < levels; i++)
+		{
+			int srcw = MAX(Width >> (i - 1), 1);
+			int srch = MAX(Height >> (i - 1), 1);
+			int w = MAX(Width >> i, 1);
+			int h = MAX(Height >> i, 1);
+
+			// Downscale
+			for (int x = 0; x < w; x++)
+			{
+				int sx0 = x * 2;
+				int sx1 = MIN((x + 1) * 2, srcw - 1);
+				for (int y = 0; y < h; y++)
+				{
+					int sy0 = y * 2;
+					int sy1 = MIN((y + 1) * 2, srch - 1);
+
+					Color4f src00 = src[sy0 + sx0 * srch];
+					Color4f src01 = src[sy1 + sx0 * srch];
+					Color4f src10 = src[sy0 + sx1 * srch];
+					Color4f src11 = src[sy1 + sx1 * srch];
+					Color4f c = (src00 + src01 + src10 + src11) * 0.25f;
+
+					dest[y + x * h] = src00;
+				}
+			}
+
+			// Sharpen filter with a 3x3 kernel:
+			for (int x = 0; x < w; x++)
+			{
+				for (int y = 0; y < h; y++)
+				{
+					Color4f c = { 0.0f, 0.0f, 0.0f, 0.0f };
+					for (int kx = -1; kx < 2; kx++)
+					{
+						for (int ky = -1; ky < 2; ky++)
+						{
+							int a = y + ky;
+							int b = x + kx;
+							if (a < 0) a = h - 1;
+							if (a == h) a = 0;
+							if (b < 0) b = w - 1;
+							if (b == h) b = 0;
+							c = c + dest[a + b * h];
+						}
+					}
+					c = c * (1.0f / 9.0f);
+					smoothed[y + x * h] = c;
+				}
+			}
+			float k = 0.04f;
+			for (int j = 0; j < w * h; j++)
+				dest[j] = dest[j] + (dest[j] - smoothed[j]) * k;
+
+			src = dest;
+			dest += w * h;
+		}
+	}
+
+	// Convert to bgra8 sRGB colorspace
+	{
+		Color4f *src = image.data() + Width * Height;
+		uint32_t *dest = PixelsBgra.data() + Width * Height;
 		for (int i = 1; i < levels; i++)
 		{
 			int w = MAX(Width >> i, 1);
 			int h = MAX(Height >> i, 1);
-
+			for (int j = 0; j < w * h; j++)
-		bicubic.ScaleImage(dest, h, w, src, Height, Width);
+			{
-
+				uint32_t a = (uint32_t)clamp(std::pow(src[j].a, 1.0f / 2.2f) * 255.0f + 0.5f, 0.0f, 255.0f);
+				uint32_t r = (uint32_t)clamp(std::pow(src[j].r, 1.0f / 2.2f) * 255.0f + 0.5f, 0.0f, 255.0f);
+				uint32_t g = (uint32_t)clamp(std::pow(src[j].g, 1.0f / 2.2f) * 255.0f + 0.5f, 0.0f, 255.0f);
+				uint32_t b = (uint32_t)clamp(std::pow(src[j].b, 1.0f / 2.2f) * 255.0f + 0.5f, 0.0f, 255.0f);
+				dest[j] = (a << 24) | (r << 16) | (g << 8) | b;
+			}
+			src += w * h;
 			dest += w * h;
 		}
+	}
 }
 
 void FTexture::GenerateBgraMipmapsFast()