Optimized mipmap generation on load.

1 files changed, 25 insertions, 41 deletions

diff --git a/dgedit/canvas.cc b/dgedit/canvas.cc
index 08005c7..4c63e5e 100644
--- a/dgedit/canvas.cc
+++ b/dgedit/canvas.cc
@@ -83,27 +83,27 @@ Canvas::~Canvas()
 #define VALU(x) (x*4+1)
 #define POWL(x) (x*4+2)
 #define POWU(x) (x*4+3)
-/*
-static void genmipmap(float *in, size_t insz, float **out, size_t *outsz)
+
+static void genmipmap(float *in, size_t insz, float *out, size_t outsz)
 {
-  *outsz = (insz / 2) * 4;
-  *out = new float[*outsz];
-  float *lookup = *out;
+  float *lookup = out;
 
-  for(size_t i = 0; i < *outsz / 4; i++) {
+  for(size_t i = 0; i < outsz; i++) {
     lookup[VALL(i)] = 0.0;
     lookup[VALU(i)] = 0.0;
     lookup[POWL(i)] = 0.0;
     lookup[POWU(i)] = 0.0;
-    for(size_t j = i * 2; j < i*2+2 && j < insz / 4; j++) {
+
+    for(size_t j = i * (insz / outsz); j < (i+1)*(insz / outsz); j++) {
       if(in[VALU(j)] > lookup[VALU(i)]) lookup[VALU(i)] = in[VALU(j)];
       if(in[VALL(j)] < lookup[VALL(i)]) lookup[VALL(i)] = in[VALL(j)];
       if(in[POWU(j)] > 0) lookup[POWU(i)] += in[POWU(j)];
       if(in[POWL(j)] < 0) lookup[POWL(i)] += in[POWL(j)];
     }
+
   }
 }
-*/
+
 void Canvas::load(QString file)
 {
   if(data) {
@@ -133,49 +133,33 @@ void Canvas::load(QString file)
 
 	sf_close(fh);
 
+  size_t lastsz = 0;
   for(size_t dev = 2; dev <= MIPMAPS; dev*=2) {
     size_t mipmapsize = size/dev;
 
     float *lookup = new float[mipmapsize * 4];
-    for(size_t i = 0; i < mipmapsize; i++) {
-      lookup[VALL(i)] = 0.0;
-      lookup[VALU(i)] = 0.0;
-      lookup[POWL(i)] = 0.0;
-      lookup[POWU(i)] = 0.0;
-      for(size_t j = i * dev; j < (i + 1) * dev; j++) {
-        if(data[j] > lookup[VALU(i)]) lookup[VALU(i)] = data[j];
-        if(data[j] < lookup[VALL(i)]) lookup[VALL(i)] = data[j];
-        if(data[j] > 0) lookup[POWU(i)] += data[j];
-        if(data[j] < 0) lookup[POWL(i)] += data[j];
+
+    if(dev == 2) {
+      for(size_t i = 0; i < mipmapsize; i++) {
+        lookup[VALL(i)] = 0.0;
+        lookup[VALU(i)] = 0.0;
+        lookup[POWL(i)] = 0.0;
+        lookup[POWU(i)] = 0.0;
+        for(size_t j = i * dev; j < (i + 1) * dev; j++) {
+          if(data[j] > lookup[VALU(i)]) lookup[VALU(i)] = data[j];
+          if(data[j] < lookup[VALL(i)]) lookup[VALL(i)] = data[j];
+          if(data[j] > 0) lookup[POWU(i)] += data[j];
+          if(data[j] < 0) lookup[POWL(i)] += data[j];
+        }
       }
+    } else {
+      genmipmap(mipmaps[dev/2], lastsz, lookup, mipmapsize);
     }
 
+    lastsz = mipmapsize;
     mipmaps[dev] = lookup;
   }
-  /*
-
-  size_t sz = (size / 2) * 4;
-  mipmaps[2] = new float[sz];
-  float *lookup = mipmaps[2];
-  for(size_t i = 0; i < sz; i++) {
-    lookup[VALL(i)] = 0.0;
-    lookup[VALU(i)] = 0.0;
-    lookup[POWL(i)] = 0.0;
-    lookup[POWU(i)] = 0.0;
-    for(size_t j = i * 2; j < (i + 1) * 2; j++) {
-      if(data[j] > lookup[VALU(i)]) lookup[VALU(i)] = data[j];
-      if(data[j] < lookup[VALL(i)]) lookup[VALL(i)] = data[j];
-      if(data[j] > 0) lookup[POWU(i)] += data[j];
-      if(data[j] < 0) lookup[POWL(i)] += data[j];
-    }
-  }
 
-  size_t dev = 3;
-  do {
-    genmipmap(mipmaps[dev], sz, &mipmaps[dev], &sz);
-    dev++;
-  } while(sz > 2);
-  */
   updateWav();
   update();
 }