由于在评论中还要求我提供 3D 方式,所以这里有一些,这是我很久以前写的一些代码的摘录。它是 OpenGL 和 C++。
每个精灵都会被要求绘制自己。使用适配器模式,我将组合精灵 - 即会有两个或多个精灵具有(0,0)相对位置,一个精灵具有所有这些“子”精灵的真实位置。
void Sprite::display (void) const
{
glBindTexture(GL_TEXTURE_2D, tex_id_);
Display::drawTranspRect(model_->getPosition().x + draw_dimensions_[0] / 2.0f,
model_->getPosition().y + draw_dimensions_[1] / 2.0f,
draw_dimensions_[0] / 2.0f, draw_dimensions_[1] / 2.0f);
}
void Display::drawTranspRect (float x, float y, float x_len, float y_len)
{
glPushMatrix();
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
glColor4f(1.0, 1.0, 1.0, 1.0);
glBegin(GL_QUADS);
glTexCoord2f(0.0f, 0.0f); glVertex3f(x - x_len, y - y_len, Z);
glTexCoord2f(1.0f, 0.0f); glVertex3f(x + x_len, y - y_len, Z);
glTexCoord2f(1.0f, 1.0f); glVertex3f(x + x_len, y + y_len, Z);
glTexCoord2f(0.0f, 1.0f); glVertex3f(x - x_len, y + y_len, Z);
glEnd();
glDisable(GL_BLEND);
glPopMatrix();
}
tex_id_
是一个整数值,用于标识用于 OpenGL 的纹理。纹理管理器的相关部分是这些。纹理管理器实际上通过检查读取的颜色是否为纯白色(RGB of (ff,ff,ff))来模拟 alpha 通道 - loadFile 代码在每像素 24 位的 BMP 文件上运行:
TextureManager::texture_id
TextureManager::createNewTexture (Texture const& tex) {
texture_id id;
glGenTextures(1, &id);
glBindTexture(GL_TEXTURE_2D, id);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexImage2D(GL_TEXTURE_2D, 0, 4, tex.width_, tex.height_, 0,
GL_BGRA_EXT, GL_UNSIGNED_BYTE, tex.texture_);
return id;
}
void TextureManager::loadImage (FILE* f, Texture& dest) const {
fseek(f, 18, SEEK_SET);
signed int compression_method;
unsigned int const HEADER_SIZE = 54;
fread(&dest.width_, sizeof(unsigned int), 1, f);
fread(&dest.height_, sizeof(unsigned int), 1, f);
fseek(f, 28, SEEK_SET);
fread(&dest.bpp_, sizeof (unsigned short), 1, f);
fseek(f, 30, SEEK_SET);
fread(&compression_method, sizeof(unsigned int), 1, f);
// We add 4 channels, because we will manually set an alpha channel
// for the color white.
dest.size_ = dest.width_ * dest.height_ * dest.bpp_/8 * 4;
dest.texture_ = new unsigned char[dest.size_];
unsigned char* buffer = new unsigned char[3 * dest.size_ / 4];
// Slurp in whole file and replace all white colors with green
// values and an alpha value of 0:
fseek(f, HEADER_SIZE, SEEK_SET);
fread (buffer, sizeof(unsigned char), 3 * dest.size_ / 4, f);
for (unsigned int count = 0; count < dest.width_ * dest.height_; count++) {
dest.texture_[0+count*4] = buffer[0+count*3];
dest.texture_[1+count*4] = buffer[1+count*3];
dest.texture_[2+count*4] = buffer[2+count*3];
dest.texture_[3+count*4] = 0xff;
if (dest.texture_[0+count*4] == 0xff &&
dest.texture_[1+count*4] == 0xff &&
dest.texture_[2+count*4] == 0xff) {
dest.texture_[0+count*4] = 0x00;
dest.texture_[1+count*4] = 0xff;
dest.texture_[2+count*4] = 0x00;
dest.texture_[3+count*4] = 0x00;
dest.uses_alpha_ = true;
}
}
delete[] buffer;
}
这实际上是我在业余时间偶尔开发的一个小型 Jump'nRun。顺便说一句,它也使用了 gluOrtho2D() 模式。如果您离开意味着与您联系,如果您愿意,我会将来源发送给您。