topical media & game development
lib-of-vs-libs-openFrameworks-graphics-ofTexture.cpp / cpp
include <ofTexture.h>
include <ofUtils.h> // for nextPow2()
include <ofAppRunner.h> // for getWidth()
static bool bTexHackEnabled = true;
//---------------------------------
void ofEnableTextureEdgeHack(){
bTexHackEnabled = true;
}
//---------------------------------
void ofDisableTectureEdgeHack(){
bTexHackEnabled = false;
}
//----------------------------------------------------------
ofTexture::ofTexture(){
texData.bAllocated = false;
texData.textureName[0] = 0;
texData.textureID = 0;
texData.bFlipTexture = false;
texData.textureTarget = GL_TEXTURE_2D;
texData.glTypeInternal = 0;
texData.glType = 0;
texData.width = 0;
texData.height = 0;
texData.tex_w = 0;
texData.tex_h = 0;
texData.tex_t = 0;
texData.tex_u = 0;
resetAnchor();
}
//----------------------------------------------------------
bool ofTexture::bAllocated(){
return texData.bAllocated;
}
//----------------------------------------------------------
ofTexture::ofTexture(const ofTexture& mom){
texData = mom.texData;
}
//----------------------------------------------------------
ofTexture& ofTexture::operator=(const ofTexture& mom){
texData = mom.texData;
return *this;
}
//----------------------------------------------------------
ofTextureData ofTexture::getTextureData(){
if(!texData.bAllocated){
ofLog(OF_LOG_ERROR, "getTextureData() - texture has not been allocated");
}
return texData;
}
//----------------------------------------------------------
ofTexture::~ofTexture(){
clear();
}
//----------------------------------------------------------
void ofTexture::clear(){
// try to free up the texture memory so we don't reallocate
// http://www.opengl.org/documentation/specs/man_pages/hardcopy/GL/html/gl/deletetextures.html
if (texData.textureName[0] != 0){
glDeleteTextures(1, (GLuint *)texData.textureName);
}
texData.bAllocated = false;
}
//----------------------------------------------------------
void ofTexture::allocate(int w, int h, int internalGlDataType){
allocate(w, h, internalGlDataType, ofGetUsingArbTex());
}
//----------------------------------------------------------
void ofTexture::allocate(int w, int h, int internalGlDataType, bool bUseARBExtention){
//our graphics card might not support arb so we have to see if it is supported.
#ifndef TARGET_OF_IPHONE
if (bUseARBExtention && GLEE_ARB_texture_rectangle){
texData.tex_w = w;
texData.tex_h = h;
texData.tex_t = w;
texData.tex_u = h;
texData.textureTarget = GL_TEXTURE_RECTANGLE_ARB;
} else
#endif
{
//otherwise we need to calculate the next power of 2 for the requested dimensions
//ie (320x240) becomes (512x256)
texData.tex_w = ofNextPow2(w);
texData.tex_h = ofNextPow2(h);
texData.tex_t = 1.0f;
texData.tex_u = 1.0f;
texData.textureTarget = GL_TEXTURE_2D;
}
texData.glTypeInternal = internalGlDataType;
// attempt to free the previous bound texture, if we can:
clear();
glGenTextures(1, (GLuint *)texData.textureName); // could be more then one, but for now, just one
glEnable(texData.textureTarget);
glBindTexture(texData.textureTarget, (GLuint)texData.textureName[0]);
#ifndef TARGET_OF_IPHONE
// can't do this on OpenGL ES: on full-blown OpenGL,
// internalGlDataType and glDataType (GL_LUMINANCE below)
// can be different; on ES they must be exactly the same.
glTexImage2D(texData.textureTarget, 0, texData.glTypeInternal, (GLint)texData.tex_w, (GLint)texData.tex_h, 0, GL_LUMINANCE, GL_UNSIGNED_BYTE, 0); // init to black...
#else
glTexImage2D(texData.textureTarget, 0, texData.glTypeInternal, texData.tex_w, texData.tex_h, 0, texData.glTypeInternal, GL_UNSIGNED_BYTE, 0);
#endif
glTexParameterf(texData.textureTarget, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameterf(texData.textureTarget, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexParameterf(texData.textureTarget, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameterf(texData.textureTarget, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
glDisable(texData.textureTarget);
texData.width = w;
texData.height = h;
#ifdef TARGET_OF_IPHONE
texData.bFlipTexture = true; // textures need to be flipped for the iphone
#else
texData.bFlipTexture = false;
#endif
texData.bAllocated = true;
}
//----------------------------------------------------------
void ofTexture::loadData(unsigned char * data, int w, int h, int glDataType){
// can we allow for uploads bigger then texture and
// just take as much as the texture can?
//
// ie:
// int uploadW = MIN(w, tex_w);
// int uploadH = MIN(h, tex_h);
// but with a "step" size of w?
// check "glTexSubImage2D"
if ( w > texData.tex_w || h > texData.tex_h) {
ofLog(OF_LOG_ERROR,"image data too big for allocated texture. not uploading...");
return;
}
//update our size with the new dimensions - this should be the same size or smaller than the allocated texture size
texData.width = w;
texData.height = h;
texData.glType = glDataType;
//compute new tex co-ords based on the ratio of data's w, h to texture w,h;
#ifndef TARGET_OF_IPHONE
if (texData.textureTarget == GL_TEXTURE_RECTANGLE_ARB){
texData.tex_t = w;
texData.tex_u = h;
} else
#endif
{
texData.tex_t = (float)(w) / (float)texData.tex_w;
texData.tex_u = (float)(h) / (float)texData.tex_h;
}
// ok this is an ultra annoying bug :
// opengl texels and linear filtering -
// when we have a sub-image, and we scale it
// we can clamp the border pixels to the border,
// but the borders of the sub image get mixed with
// neighboring pixels...
// grr...
//
// the best solution would be to pad out the image
// being uploaded with 2 pixels on all sides, and
// recompute tex_t coordinates..
// another option is a gl_arb non pow 2 textures...
// the current hack is to alter the tex_t, tex_u calcs, but
// that makes the image slightly off...
// this is currently being done in draw...
//
// we need a good solution for this..
//
// http://www.opengl.org/discussion_boards/ubb/ultimatebb.php?ubb=get_topic;f=3;t=014770#000001
// http://www.opengl.org/discussion_boards/ubb/ultimatebb.php?ubb=get_topic;f=3;t=014770#000001
//------------------------ likely, we are uploading continuous data
GLint prevAlignment;
glGetIntegerv(GL_UNPACK_ALIGNMENT, &prevAlignment);
glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
// update the texture image:
glEnable(texData.textureTarget);
glBindTexture(texData.textureTarget, (GLuint)texData.textureName[0]);
glTexSubImage2D(texData.textureTarget,0,0,0,w,h,texData.glType,GL_UNSIGNED_BYTE,data);
glDisable(texData.textureTarget);
//------------------------ back to normal.
glPixelStorei(GL_UNPACK_ALIGNMENT, prevAlignment);
#ifdef TARGET_OF_IPHONE
texData.bFlipTexture = true; // textures need to be flipped for the iphone
#else
texData.bFlipTexture = false;
#endif
}
//----------------------------------------------------------
void ofTexture::loadScreenData(int x, int y, int w, int h){
int screenHeight = ofGetHeight();
y = screenHeight - y;
y -= h; // top, bottom issues
texData.bFlipTexture = true;
if ( w > texData.tex_w || h > texData.tex_h) {
ofLog(OF_LOG_ERROR,"image data too big for allocated texture. not uploading...");
return;
}
//update our size with the new dimensions - this should be the same size or smaller than the allocated texture size
texData.width = w;
texData.height = h;
texData.glType = GL_RGB;
//compute new tex co-ords based on the ratio of data's w, h to texture w,h;
#ifndef TARGET_OF_IPHONE // DAMIAN
if (texData.textureTarget == GL_TEXTURE_RECTANGLE_ARB){
texData.tex_t = (float)(w);
texData.tex_u = (float)(h);
} else
#endif
{
texData.tex_t = (float)(w) / (float)texData.tex_w;
texData.tex_u = (float)(h) / (float)texData.tex_h;
}
glEnable(texData.textureTarget);
glBindTexture(texData.textureTarget, (GLuint)texData.textureName[0]);
glCopyTexSubImage2D(texData.textureTarget, 0,0,0,x,y,w,h);
glDisable(texData.textureTarget);
}
//we could cap these values - but it might be more useful
//to be able to set anchor points outside the image
//----------------------------------------------------------
void ofTexture::setAnchorPercent(float xPct, float yPct){
anchor.x = xPct;
anchor.y = yPct;
bAnchorIsPct = true;
}
//----------------------------------------------------------
void ofTexture::setAnchorPoint(int x, int y){
anchor.x = x;
anchor.y = y;
bAnchorIsPct = false;
}
//----------------------------------------------------------
void ofTexture::resetAnchor(){
anchor = 0;
bAnchorIsPct = false;
}
//----------------------------------------------------------
void ofTexture::bind(){
//we could check if it has been allocated - but we don't do that in draw()
glEnable(texData.textureTarget);
glBindTexture( texData.textureTarget, (GLuint)texData.textureName[0]);
}
//----------------------------------------------------------
void ofTexture::unbind(){
glDisable(texData.textureTarget);
}
//----------------------------------------------------------
void ofTexture::draw(float x, float y, float w, float h){
glEnable(texData.textureTarget);
// bind the texture
glBindTexture( texData.textureTarget, (GLuint)texData.textureName[0] );
GLfloat px0 = 0; // up to you to get the aspect ratio right
GLfloat py0 = 0;
GLfloat px1 = w;
GLfloat py1 = h;
if (texData.bFlipTexture == true){
GLint temp = (GLint)py0;
py0 = py1;
py1 = temp;
}
// for rect mode center, let's do this:
if (ofGetRectMode() == OF_RECTMODE_CENTER){
px0 = -w/2;
py0 = -h/2;
px1 = +w/2;
py1 = +h/2;
}
//we translate our drawing points by our anchor point.
//we still respect ofRectMode so if you have rect mode set to
//OF_RECTMODE_CENTER your anchor will be relative to that.
GLfloat anchorX;
GLfloat anchorY;
if(bAnchorIsPct){
anchorX = anchor.x * w;
anchorY = anchor.y * h;
}else{
anchorX = anchor.x;
anchorY = anchor.y;
}
px0 -= anchorX;
py0 -= anchorY;
px1 -= anchorX;
py1 -= anchorY;
// -------------------------------------------------
// complete hack to remove border artifacts.
// slightly, slightly alters an image, scaling...
// to remove the border.
// we need a better solution for this, but
// to constantly add a 2 pixel border on all uploaded images
// is insane..
GLfloat offsetw = 0;
GLfloat offseth = 0;
if (texData.textureTarget == GL_TEXTURE_2D && bTexHackEnabled) {
offsetw = 1.0f / (texData.tex_w);
offseth = 1.0f / (texData.tex_h);
}
// -------------------------------------------------
GLfloat tx0 = 0+offsetw;
GLfloat ty0 = 0+offseth;
GLfloat tx1 = texData.tex_t - offsetw;
GLfloat ty1 = texData.tex_u - offseth;
glPushMatrix();
glTranslatef(x,y,0.0f);
GLfloat tex_coords[] = {
tx0,ty0,
tx1,ty0,
tx1,ty1,
tx0,ty1
};
GLfloat verts[] = {
px0,py0,
px1,py0,
px1,py1,
px0,py1
};
glEnableClientState( GL_TEXTURE_COORD_ARRAY );
glTexCoordPointer(2, GL_FLOAT, 0, tex_coords );
glEnableClientState(GL_VERTEX_ARRAY);
glVertexPointer(2, GL_FLOAT, 0, verts );
glDrawArrays( GL_TRIANGLE_FAN, 0, 4 );
glDisableClientState( GL_TEXTURE_COORD_ARRAY );
glPopMatrix();
glDisable(texData.textureTarget);
}
//----------------------------------------------------------
void ofTexture::draw(float x, float y){
draw(x,y,texData.width, texData.height);
}
//----------------------------------------------------------
float ofTexture::getHeight(){
return texData.height;
}
//----------------------------------------------------------
float ofTexture::getWidth(){
return texData.width;
}
(C) Æliens
04/09/2009
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