From 2dd7568047c7b0af8a7c8a656f1bb6708fb856c6 Mon Sep 17 00:00:00 2001
From: Bjørn Lindeijer <bjorn@lindeijer.nl>
Date: Tue, 20 Mar 2007 23:26:28 +0000
Subject: Reduced amount of useless logging, calculate nearest power of two in
 a function and only do the alpha check in software mode.

---
 src/resources/image.cpp | 81 +++++++++++++++++++++++++++----------------------
 src/resources/image.h   |  6 ++++
 2 files changed, 50 insertions(+), 37 deletions(-)

(limited to 'src/resources')

diff --git a/src/resources/image.cpp b/src/resources/image.cpp
index a7c81574..e2220088 100644
--- a/src/resources/image.cpp
+++ b/src/resources/image.cpp
@@ -80,7 +80,7 @@ Image* Image::load(void *buffer, unsigned int bufferSize,
         tmpImage = IMG_Load_RW(rw, 1);
     }
 
-    if (tmpImage == NULL) {
+    if (!tmpImage) {
         logger->log("Error, image load failed: %s", IMG_GetError());
         return NULL;
     }
@@ -99,49 +99,28 @@ Image* Image::load(void *buffer, unsigned int bufferSize,
     amask = 0xff000000;
 #endif
 
-    bool hasAlpha = false;
-
-    // Figure out whether the image uses its alpha layer
-    for (int i = 0; i < tmpImage->w * tmpImage->h; ++i)
-    {
-        Uint8 r, g, b, a;
-        SDL_GetRGBA(
-                ((Uint32*) tmpImage->pixels)[i],
-                tmpImage->format,
-                &r, &g, &b, &a);
-
-        if (a != 255)
-        {
-            hasAlpha = true;
-            break;
-        }
-    }
-
-    if (hasAlpha) {
-        SDL_SetAlpha(tmpImage, SDL_SRCALPHA, SDL_ALPHA_OPAQUE);
-    }
-
 #ifdef USE_OPENGL
     if (mUseOpenGL)
     {
         int width = tmpImage->w;
         int height = tmpImage->h;
-        int realWidth = 1, realHeight = 1;
+        int realWidth = powerOfTwo(width);
+        int realHeight = powerOfTwo(height);
 
-        while (realWidth < width && realWidth < 1024) {
-            realWidth *= 2;
-        }
-
-        while (realHeight < height && realHeight < 1024) {
-            realHeight *= 2;
+        if (realWidth < width || realHeight < height)
+        {
+            logger->log("Warning: image too large, cropping to %dx%d texture!",
+                    tmpImage->w, tmpImage->h);
         }
 
+        // Make sure the alpha channel is not used, but copied to destination
         SDL_SetAlpha(tmpImage, 0, SDL_ALPHA_OPAQUE);
+
         SDL_Surface *oldImage = tmpImage;
-        tmpImage = SDL_CreateRGBSurface(SDL_SWSURFACE, realWidth, realHeight, 32,
-                rmask, gmask, bmask, amask);
+        tmpImage = SDL_CreateRGBSurface(SDL_SWSURFACE, realWidth, realHeight,
+            32, rmask, gmask, bmask, amask);
 
-        if (tmpImage == NULL) {
+        if (!tmpImage) {
             logger->log("Error, image convert failed: out of memory");
             return NULL;
         }
@@ -151,8 +130,6 @@ Image* Image::load(void *buffer, unsigned int bufferSize,
 
         GLuint texture;
         glGenTextures(1, &texture);
-        logger->log("Binding texture %d (%dx%d)",
-                texture, tmpImage->w, tmpImage->h);
         glBindTexture(GL_TEXTURE_2D, texture);
 
         if (SDL_MUSTLOCK(tmpImage)) {
@@ -208,6 +185,24 @@ Image* Image::load(void *buffer, unsigned int bufferSize,
     }
 #endif
 
+    bool hasAlpha = false;
+
+    // Figure out whether the image uses its alpha layer
+    for (int i = 0; i < tmpImage->w * tmpImage->h; ++i)
+    {
+        Uint8 r, g, b, a;
+        SDL_GetRGBA(
+                ((Uint32*) tmpImage->pixels)[i],
+                tmpImage->format,
+                &r, &g, &b, &a);
+
+        if (a != 255)
+        {
+            hasAlpha = true;
+            break;
+        }
+    }
+
     SDL_Surface *image;
 
     // Convert the surface to the current display format
@@ -219,7 +214,7 @@ Image* Image::load(void *buffer, unsigned int bufferSize,
     }
     SDL_FreeSurface(tmpImage);
 
-    if (image == NULL) {
+    if (!image) {
         logger->log("Error: Image convert failed.");
         return NULL;
     }
@@ -278,10 +273,22 @@ float Image::getAlpha()
 }
 
 #ifdef USE_OPENGL
-void Image::setLoadAsOpenGL(bool useOpenGL)
+void
+Image::setLoadAsOpenGL(bool useOpenGL)
 {
     Image::mUseOpenGL = useOpenGL;
 }
+
+int
+Image::powerOfTwo(int input)
+{
+    int value = 1;
+    while (value < input && value < 1024)
+    {
+        value <<= 1;
+    }
+    return value;
+}
 #endif
 
 //============================================================================
diff --git a/src/resources/image.h b/src/resources/image.h
index c769ecb6..1bdfbf48 100644
--- a/src/resources/image.h
+++ b/src/resources/image.h
@@ -123,6 +123,12 @@ class Image : public Resource
 #ifdef USE_OPENGL
         Image(const std::string &idPath, GLuint glimage, int width, int height,
                 int texWidth, int texHeight);
+
+        /**
+         * Returns the first power of two equal or bigger than the input.
+         */
+        static int
+        powerOfTwo(int input);
 #endif
         Image(const std::string &idPath, SDL_Surface *image);
 
-- 
cgit v1.2.3-70-g09d2