From 52ba7a652f9e84425f328719fe6fba138361b4b3 Mon Sep 17 00:00:00 2001
From: Jasper van de Gronde <jasper.vandegronde@gmail.com>
Date: Tue, 31 Mar 2009 20:41:47 +0000
Subject: Fix for helperfns_read_vector (which could go on trying to read
 numbers for ever) and some quality improvements to gradient rendering and
 feComponentTransfer handling.

(bzr r7599)
---
 src/display/nr-filter-component-transfer.cpp | 102 +++++++++++++++++++--------
 1 file changed, 72 insertions(+), 30 deletions(-)

(limited to 'src/display')

diff --git a/src/display/nr-filter-component-transfer.cpp b/src/display/nr-filter-component-transfer.cpp
index 74d66fbe4..6f9e2b712 100644
--- a/src/display/nr-filter-component-transfer.cpp
+++ b/src/display/nr-filter-component-transfer.cpp
@@ -45,13 +45,10 @@ int FilterComponentTransfer::render(FilterSlot &slot, FilterUnits const &/*units
     int y0=in->area.y0;
     int y1=in->area.y1;
 
-    NRPixBlock *out = new NRPixBlock;
-    nr_pixblock_setup_fast(out, NR_PIXBLOCK_MODE_R8G8B8A8N, x0, y0, x1, y1, true);
-
-    // this primitive is defined for non-premultiplied RGBA values,
+    // this primitive is defined for RGBA values,
     // thus convert them to that format before blending
     bool free_in_on_exit = false;
-    if (in->mode != NR_PIXBLOCK_MODE_R8G8B8A8N) {
+    if (in->mode != NR_PIXBLOCK_MODE_R8G8B8A8N && in->mode != NR_PIXBLOCK_MODE_R8G8B8A8P) {
         NRPixBlock *original_in = in;
         in = new NRPixBlock;
         nr_pixblock_setup_fast(in, NR_PIXBLOCK_MODE_R8G8B8A8N,
@@ -61,6 +58,11 @@ int FilterComponentTransfer::render(FilterSlot &slot, FilterUnits const &/*units
         nr_blit_pixblock_pixblock(in, original_in);
         free_in_on_exit = true;
     }
+    bool premultiplied = in->mode == NR_PIXBLOCK_MODE_R8G8B8A8P;
+    g_message("Premultiplied=%s", premultiplied?"yes":"no");
+
+    NRPixBlock *out = new NRPixBlock;
+    nr_pixblock_setup_fast(out, in->mode, x0, y0, x1, y1, true);
 
     unsigned char *in_data = NR_PIXBLOCK_PX(in);
     unsigned char *out_data = NR_PIXBLOCK_PX(out);
@@ -71,7 +73,8 @@ int FilterComponentTransfer::render(FilterSlot &slot, FilterUnits const &/*units
     int size = 4 * (y1-y0) * (x1-x0);
     int i;
 
-    for (int color=0;color<4;color++){
+    int color=4;
+    while(color-->0) {
         int _vsize = tableValues[color].size();
         double _intercept = intercept[color];
         double _slope = slope[color];
@@ -93,15 +96,28 @@ int FilterComponentTransfer::render(FilterSlot &slot, FilterUnits const &/*units
                         out_data[i]=in_data[i];
                     }
                 } else {
-                    std::vector<gdouble> _tableValues(tableValues[color]);
-                    // Scale by 255 and add .5 to avoid having to add it later for rounding purposes
-                    for(i=0;i<_vsize;i++) {
-                        _tableValues[i] = std::max(0.,std::min(255.,255*_tableValues[i])) + .5;
-                    }
-                    for(i=color;i<size;i+=4){
-                        int k = FAST_DIVIDE<255>((_vsize-1) * in_data[i]);
-                        double dx = ((_vsize-1) * in_data[i])/255.0 - k;
-                        out_data[i] = static_cast<unsigned char>(_tableValues[k] + dx * (_tableValues[k+1] - _tableValues[k]));
+                    if (!premultiplied || color==3) {
+                        std::vector<gdouble> _tableValues(tableValues[color]);
+                        // Scale by 255 and add .5 to avoid having to add it later for rounding purposes
+                        for(i=0;i<_vsize;i++) {
+                            _tableValues[i] = std::max(0.,std::min(255.,255*_tableValues[i])) + .5;
+                        }
+                        for(i=color;i<size;i+=4){
+                            int k = FAST_DIVIDE<255>((_vsize-1) * in_data[i]);
+                            double dx = ((_vsize-1) * in_data[i])/255.0 - k;
+                            out_data[i] = static_cast<unsigned char>(_tableValues[k] + dx * (_tableValues[k+1] - _tableValues[k]));
+                        }
+                    } else {
+                        std::vector<gdouble> _tableValues(tableValues[color]);
+                        for(i=0;i<_vsize;i++) {
+                            _tableValues[i] = std::max(0.,std::min(1.,_tableValues[i]));
+                        }
+                        for(i=color;i<size;i+=4){
+                            if (in_data[i+3-color]==0) continue;
+                            int k = ((_vsize-1) * in_data[i]) / in_data[i+3-color];
+                            double dx = ((_vsize-1) * in_data[i]) / (double)in_data[i+3-color] - k;
+                            out_data[i] = static_cast<unsigned char>(out_data[i+3-color] * (_tableValues[k] + dx * (_tableValues[k+1] - _tableValues[k])) + .5);
+                        }
                     }
                 }
                 break;
@@ -111,28 +127,54 @@ int FilterComponentTransfer::render(FilterSlot &slot, FilterUnits const &/*units
                         out_data[i] = in_data[i];
                     }
                 } else {
-                    std::vector<unsigned char> _tableValues(_vsize);
-                    // Convert to unsigned char
-                    for(i=0;i<_vsize;i++) {
-                        _tableValues[i] = static_cast<unsigned char>(std::max(0.,std::min(255.,255*tableValues[color][i])) + .5);
-                    }
-                    for(i=color;i<size;i+=4){
-                        int k = FAST_DIVIDE<255>((_vsize-1) * in_data[i]);
-                        out_data[i] =  _tableValues[k];
+                    if (!premultiplied || color==3) {
+                        std::vector<unsigned char> _tableValues(_vsize);
+                        // Convert to unsigned char
+                        for(i=0;i<_vsize;i++) {
+                            _tableValues[i] = static_cast<unsigned char>(std::max(0.,std::min(255.,255*tableValues[color][i])) + .5);
+                        }
+                        for(i=color;i<size;i+=4){
+                            int k = FAST_DIVIDE<255>((_vsize-1) * in_data[i]);
+                            out_data[i] =  _tableValues[k];
+                        }
+                    } else {
+                        std::vector<gdouble> _tableValues(tableValues[color]);
+                        for(i=0;i<_vsize;i++) {
+                            _tableValues[i] = std::max(0.,std::min(1.,_tableValues[i]));
+                        }
+                        for(i=color;i<size;i+=4){
+                            if (in_data[i+3-color]==0) continue;
+                            int k = ((_vsize-1) * in_data[i]) / in_data[i+3-color];
+                            out_data[i] =  static_cast<unsigned char>(out_data[i+3-color] * _tableValues[k] + .5);
+                        }
                     }
                 }
                 break;
             case COMPONENTTRANSFER_TYPE_LINEAR:
-                _intercept = 255*_intercept + .5;
-                for(i=color;i<size;i+=4){
-                    out_data[i] = CLAMP_D_TO_U8(_slope * in_data[i] + _intercept);
+                if (!premultiplied || color==3) {
+                    _intercept = 255*_intercept + .5;
+                    for(i=color;i<size;i+=4){
+                        out_data[i] = CLAMP_D_TO_U8(_slope * in_data[i] + _intercept);
+                    }
+                } else {
+                    for(i=color;i<size;i+=4){
+                        if (in_data[i+3-color]==0) continue;
+                        out_data[i] = CLAMP_D_TO_U8(out_data[i+3-color] * (_slope * in_data[i] / in_data[i+3-color] + _intercept) + .5);
+                    }
                 }
                 break;
             case COMPONENTTRANSFER_TYPE_GAMMA:
-                _amplitude *= pow(255.0, -_exponent+1);
-                _offset = 255*_offset + .5;
-                for(i=color;i<size;i+=4){
-                    out_data[i] = CLAMP_D_TO_U8(_amplitude * pow((double)in_data[i], _exponent) + _offset);
+                if (!premultiplied || color==3) {
+                    _amplitude *= pow(255.0, -_exponent+1); // The input should be divided by 255, then exponentiated and then multiplied by 255 again, instead the amplitude is modified accordingly.
+                    _offset = 255*_offset + .5;
+                    for(i=color;i<size;i+=4){
+                        out_data[i] = CLAMP_D_TO_U8(_amplitude * pow((double)in_data[i], _exponent) + _offset);
+                    }
+                } else {
+                    for(i=color;i<size;i+=4){
+                        if (in_data[i+3-color]==0) continue;
+                        out_data[i] = CLAMP_D_TO_U8(out_data[i+3-color] * (_amplitude * pow((double)in_data[i] / in_data[i+3-color], _exponent) + _offset) + .5);
+                    }
                 }
                 break;
             case COMPONENTTRANSFER_TYPE_ERROR:
-- 
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