From 4d69b79ca72a805c57242db576ece5d0835ef5ec Mon Sep 17 00:00:00 2001
From: gmiranda <gmiranda@db09e94b-7117-0410-a7e6-85ae5ff6e0e9>
Date: Fri, 28 Jul 2006 12:46:49 +0000
Subject: [PATCH] I implemented a new blur algorithm. Works better, but there's
 something in the second pass that introduces more dots.

git-svn-id: https://svn.code.sf.net/p/q3cellshading/code/trunk@26 db09e94b-7117-0410-a7e6-85ae5ff6e0e9
---
 code/renderer/tr_image.c | 201 +++++++++++++++++++--------------------
 1 file changed, 100 insertions(+), 101 deletions(-)

diff --git a/code/renderer/tr_image.c b/code/renderer/tr_image.c
index bdd1ddb..fad6036 100644
--- a/code/renderer/tr_image.c
+++ b/code/renderer/tr_image.c
@@ -839,110 +839,109 @@ for(row=rows-1; row>=arow+3; row--)
 
 #define DIVNUM 15
 
+
+/**
+ * 2 passes blur filter
+ * @see http://www.filtermeister.com/tutorials/blur02.html
+ */
+
 void blur(int columns, int rows, byte *targa_rgba)
 {
-	int		row, column;
-	float red,green,blue;
-	float ared,agreen,ablue;
-	
-	ared=agreen=ablue=128;
-	
-		//for(row=rows-1; row>=0; row--) 
-		for(row=0; row<rows; row++) 
-		{
-			//pixbuf = targa_rgba + row*columns*4;
-			for(column=0; column<columns; column++) 
-			{
-				red=0;
-				red+=getImageR(targa_rgba,column-1,row-1,columns,rows);
-				red+=getImageR(targa_rgba,column,row-1,columns,rows);
-				red+=getImageR(targa_rgba,column+1,row-1,columns,rows);
-				red+=getImageR(targa_rgba,column-1,row,columns,rows);
-				red+=getImageR(targa_rgba,column,row,columns,rows);
-				red+=getImageR(targa_rgba,column+1,row,columns,rows);
-				red+=getImageR(targa_rgba,column-1,row+1,columns,rows);
-				red+=getImageR(targa_rgba,column,row+1,columns,rows);
-				red+=getImageR(targa_rgba,column+1,row+1,columns,rows);
-				
-				red/=9;
-				red*=2;
-				red+=ared;
-				red/=3;
-				
-				red=(int)red/DIVNUM;
-				red*=DIVNUM;
-				red+=(DIVNUM/2);
-				ared=red;
-				
-				setImageR(targa_rgba, column, row, columns, rows, (byte)red);
-				////////////////////
-							green=0;
-				green+=getImageG(targa_rgba,column-1,row-1,columns,rows);
-				green+=getImageG(targa_rgba,column,row-1,columns,rows);
-				green+=getImageG(targa_rgba,column+1,row-1,columns,rows);
-				green+=getImageG(targa_rgba,column-1,row,columns,rows);
-				green+=getImageG(targa_rgba,column,row,columns,rows);
-				green+=getImageG(targa_rgba,column+1,row,columns,rows);
-				green+=getImageG(targa_rgba,column-1,row+1,columns,rows);
-				green+=getImageG(targa_rgba,column,row+1,columns,rows);
-				green+=getImageG(targa_rgba,column+1,row+1,columns,rows);
-				
-				green/=9;
-				green*=2;
-				green+=agreen;
-				green/=3;
-				
-				green=(int)green/DIVNUM;
-				green*=DIVNUM;
-				green+=(DIVNUM/2);
-				agreen=green;
-				setImageG(targa_rgba, column, row, columns, rows, (byte)green);
-				////////////////////////
-							blue=0;
-				blue+=getImageB(targa_rgba,column-1,row-1,columns,rows);
-				blue+=getImageB(targa_rgba,column,row-1,columns,rows);
-				blue+=getImageB(targa_rgba,column+1,row-1,columns,rows);
-				blue+=getImageB(targa_rgba,column-1,row,columns,rows);
-				blue+=getImageB(targa_rgba,column,row,columns,rows);
-				blue+=getImageB(targa_rgba,column+1,row,columns,rows);
-				blue+=getImageB(targa_rgba,column-1,row+1,columns,rows);
-				blue+=getImageB(targa_rgba,column,row+1,columns,rows);
-				blue+=getImageB(targa_rgba,column+1,row+1,columns,rows);
-				
-				blue/=9;
-				
-				blue*=2;
-				blue+=ablue;
-				blue/=3;
-				
-				blue=(int)blue/DIVNUM;
-				blue*=DIVNUM;
-				blue+=(DIVNUM/2);
-				
-				ablue=blue;
-				setImageB(targa_rgba, column, row, columns, rows, (byte)blue);
-				
-				// "halftoning"
-				/*if((row%5==0)&&(column%5==1))
+
+		// 4x4 kernel
+	int	kernelwidth = 4, kernelheight = 4,
+		x, y, z, xlook, ylook,
+		sum, amount,
+		// number of channels (R,G,B, skip alpha)
+		channels = 3;
+
+	// Temporary image
+	byte*	t;
+
+	// Allocate
+	t = (byte*)malloc(sizeof(byte)*rows*columns*4);
+
+	// First pass
+	for (y=0; y < rows; y++){
+		for (x=0; x < columns; x++){
+			for (z= 0; z < channels; z++) {
+				sum=0; amount=0;
+				for (xlook=0; xlook<kernelwidth; xlook++)
 				{
-					gris=0;
-					gris+=red;
-					gris+=green;
-					gris+=blue;
-					gris/=3;
-					
-					gris=255-gris;
-					if(gris<0)
-						gris=0;
-						
-						setImageR(targa_rgba, column, row, columns, rows, (byte)gris);
-						setImageG(targa_rgba, column, row, columns, rows, (byte)gris);
-						setImageB(targa_rgba, column, row, columns, rows, (byte)gris);
-					
-				}*/
-			
+					switch(z){
+						case 0:
+							sum += getImageR(targa_rgba, (x+xlook-kernelwidth/2), y, columns, rows);
+							break;
+						case 1:
+							sum += getImageG(targa_rgba, (x+xlook-kernelwidth/2), y, columns, rows);
+							break;
+						case 2:
+							sum += getImageB(targa_rgba, (x+xlook-kernelwidth/2), y, columns, rows);
+							break;
+					}
+					//sum+= src((x+xlook-kernelwidth/2),y,z);
+					amount++;
+				}; //accumulate pixels in a raw
+				switch(z){
+					// R
+					case 0:
+						setImageR(t,x,y,columns,rows,(byte)(sum/amount));
+						break;
+					// G
+					case 1:
+						setImageG(t,x,y,columns,rows,(byte)(sum/amount));
+						break;
+					// B
+					case 2:
+						setImageB(t,x,y,columns,rows,(byte)(sum/amount));
+						break;
+
+				}
 			}
 		}
+	}
+	// Second pass
+	for (y=0; y < rows; y++) {
+		for (x=0; x < columns; x++) {
+			for (z= 0; z < channels; z++) {
+				sum=0; amount=0;
+				for (ylook=0; ylook<kernelheight; ylook++)
+				{
+					switch(z){
+						case 0:
+							sum+= getImageR(t,x,(y+ylook-kernelheight/2),columns,rows);
+							break;
+						case 1:
+							sum+= getImageG(t,x,(y+ylook-kernelheight/2),columns,rows);
+							break;
+						case 2:
+							sum+= getImageB(t,x,(y+ylook-kernelheight/2),columns,rows);
+							break;
+					}
+					amount++;
+				}; //accumulate pixels in a column
+				switch(z){
+					// R
+					case 0:
+						setImageR(targa_rgba,x,y,columns,rows,(byte)(sum/amount)); //divide the sum onto kernel size
+						break;
+					// G
+					case 1:
+						setImageG(targa_rgba,x,y,columns,rows,(byte)(sum/amount)); //divide the sum onto kernel size
+						break;
+					// B
+					case 2:
+						setImageB(targa_rgba,x,y,columns,rows,(byte)(sum/amount)); //divide the sum onto kernel size
+						break;
+				}
+
+			}
+		}
+	}
+
+	free(t);
+
+
 }
 
 
@@ -1024,7 +1023,7 @@ void kuwahara(int columns, int rows, byte *targa_rgba)
 	float var, min;
 	float** mean, **variance;
 
-	//blur(columns, rows, targa_rgba);
+	blur(columns, rows, targa_rgba);
 
 	// I hate malloc I hate malloc I hate malloc I hate malloc I hate malloc I hate malloc 
 	mean = (float**)malloc(sizeof(float*)*width2);
@@ -1126,7 +1125,7 @@ void kuwahara(int columns, int rows, byte *targa_rgba)
 		free(variance[index2]);
 	free(variance);
 	
-	blur(columns, rows, targa_rgba);  
+	//blur(columns, rows, targa_rgba);  
    }
 
 //RED