From e6e1e5deb60ccbb4fa175066820d81ad1bf1cefa Mon Sep 17 00:00:00 2001
From: John Tsiombikas <nuclear@mutantstargoat.com>
Date: Thu, 8 Dec 2016 02:41:55 +0200
Subject: [PATCH] added the capability to crudely resize images by half in
 image.cc

---
 src/app.cc     |    6 ++++++
 src/image.cc   |   28 ++++++++++++++++++++++++++++
 src/image.h    |    2 ++
 src/texture.cc |   14 ++++++++++----
 4 files changed, 46 insertions(+), 4 deletions(-)

diff --git a/src/app.cc b/src/app.cc
index ca750fa..e135ddf 100644
--- a/src/app.cc
+++ b/src/app.cc
@@ -574,6 +574,7 @@ static void toggle_flight()
 
 static void calc_framerate()
 {
+	static int ncalc;
 	static int nframes;
 	static long prev_upd;
 
@@ -582,6 +583,11 @@ static void calc_framerate()
 		framerate = (float)nframes / (float)(elapsed * 0.001);
 		nframes = 1;
 		prev_upd = time_msec;
+
+		if(++ncalc >= 5) {
+			printf("fps: %f\n", framerate);
+			ncalc = 0;
+		}
 	} else {
 		++nframes;
 	}
diff --git a/src/image.cc b/src/image.cc
index c245212..e79073d 100644
--- a/src/image.cc
+++ b/src/image.cc
@@ -143,6 +143,34 @@ void Image::rotate_180()
 	flip_horizontal();
 }
 
+void Image::resize_half()
+{
+	int pixsz = pixel_size(fmt);
+	int newxsz = width / 2;
+	int newysz = height / 2;
+
+	if(!newxsz || !newysz) return;
+
+	unsigned char *newpix = new unsigned char[newxsz * newysz * pixsz];
+
+	unsigned char *sptr = (unsigned char*)pixels;
+	unsigned char *dptr = newpix;
+
+	for(int i=0; i<newysz; i++) {
+		if(i & 1) sptr += width * pixsz;
+		for(int j=0; j<newxsz; j++) {
+			memcpy(dptr, sptr, pixsz);
+			dptr += pixsz;
+			sptr += pixsz * 2;
+		}
+	}
+
+	delete [] (char*)pixels;
+	pixels = newpix;
+	width = newxsz;
+	height = newysz;
+}
+
 bool Image::load(const char *fname)
 {
 	struct img_pixmap pixmap;
diff --git a/src/image.h b/src/image.h
index 9d66825..1d16979 100644
--- a/src/image.h
+++ b/src/image.h
@@ -40,6 +40,8 @@ public:
 	void flip_vertical();
 	void rotate_180();
 
+	void resize_half();
+
 	bool load(const char *fname);
 	bool save(const char *fname) const;
 };
diff --git a/src/texture.cc b/src/texture.cc
index dae0c7c..ff4d1b5 100644
--- a/src/texture.cc
+++ b/src/texture.cc
@@ -245,6 +245,8 @@ void Texture::set_image_2d(const Image &img)
 	glTexParameteri(target, GL_TEXTURE_WRAP_S, GL_REPEAT);
 	glTexParameteri(target, GL_TEXTURE_WRAP_T, GL_REPEAT);
 
+	glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
+
 #ifdef __GLEW_H__
 	if(GLEW_SGIS_generate_mipmap) {
 		glTexParameteri(target, GL_GENERATE_MIPMAP_SGIS, GL_TRUE);
@@ -263,6 +265,7 @@ void Texture::set_image_2d(const Image &img)
 
 bool Texture::set_image_cube(const Image &img, int idx)
 {
+	unsigned int err;
 	if(idx < 0 || idx >= 6) {
 		return false;
 	}
@@ -276,7 +279,10 @@ bool Texture::set_image_cube(const Image &img, int idx)
 
 	target = GL_TEXTURE_CUBE_MAP;
 	glBindTexture(target, id);
-	assert(glGetError() == GL_NO_ERROR);
+	if((err = glGetError()) == GL_INVALID_OPERATION) {
+		return false;	// probably not a cubemap
+	}
+	assert(err == GL_NO_ERROR);
 	glTexParameteri(target, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 	glTexParameteri(target, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
 	glTexParameteri(target, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
@@ -301,15 +307,15 @@ bool Texture::set_image_cube(const Image &img)
 	int xsz = img.get_width();
 	int ysz = img.get_height();
 
-	if(xsz / 4 == ysz / 3) {
+	if((xsz << 8) / 4 == (ysz << 8) / 3) {
 		// horizontal cross, assume the vertical bit is center-left
 		return set_cube_multi(img, hcross[0], hcross[1], xsz / 4);
 	}
-	if(xsz / 3 == ysz / 4) {
+	if((xsz << 8) / 3 == (ysz << 8) / 4) {
 		// vertical cross, assume the horizontal bit is center-top (180-rotated image 5)
 		return set_cube_multi(img, vcross[0], vcross[1], ysz / 4, (1 << 5));
 	}
-	if(xsz / 3 == ysz / 2) {
+	if((xsz << 8) / 3 == (ysz << 8) / 2) {
 		// horizontal sixpack
 		return set_cube_multi(img, hsix[0], hsix[1], ysz / 2);
 	}
-- 
1.7.10.4