#include <stdio.h>
#include <stdlib.h>
#ifdef __DREAMCAST__
#include <kos.h>
#endif
#include "GL/gl.h"
#include "GL/glu.h"
#include "GL/glkos.h"
#include "GL/glext.h"
#ifdef __DREAMCAST__
extern uint8 romdisk[];
KOS_INIT_ROMDISK(romdisk);
#endif
/* floats for x rotation, y rotation, z rotation */
float xrot, yrot, zrot;
/* storage for one texture */
int texture[1];
/* Image type - contains height, width, and data */
struct Image {
unsigned long sizeX;
unsigned long sizeY;
char *data;
GLenum internalFormat;
GLboolean mipmapped;
unsigned int dataSize;
};
typedef struct Image Image;
int ImageLoad(char *filename, Image *image) {
FILE* file = NULL;
// make sure the file is there.
if ((file = fopen(filename, "rb")) == NULL)
{
printf("File Not Found : %s\n",filename);
return 0;
}
struct {
char id[4]; // 'DTEX'
GLushort width;
GLushort height;
GLuint type;
GLuint size;
} header;
fread(&header, sizeof(header), 1, file);
GLboolean twiddled = (header.type & (1 << 26)) < 1;
GLboolean compressed = (header.type & (1 << 30)) > 0;
GLboolean mipmapped = (header.type & (1 << 31)) > 0;
GLboolean strided = (header.type & (1 << 25)) > 0;
GLuint format = (header.type >> 27) & 0b111;
image->data = (char *) malloc (header.size);
image->sizeX = header.width;
image->sizeY = header.height;
image->dataSize = header.size;
GLuint expected = 2 * header.width * header.height;
GLuint ratio = (GLuint) (((GLfloat) expected) / ((GLfloat) header.size));
fread(image->data, image->dataSize, 1, file);
fclose(file);
if(compressed) {
if(twiddled) {
switch(format) {
case 0: {
if(mipmapped) {
image->internalFormat = GL_COMPRESSED_ARGB_1555_VQ_MIPMAP_TWID_KOS;
} else {
image->internalFormat = GL_COMPRESSED_ARGB_1555_VQ_TWID_KOS;
}
} break;
case 1: {
if(mipmapped) {
image->internalFormat = GL_COMPRESSED_RGB_565_VQ_MIPMAP_TWID_KOS;
} else {
image->internalFormat = GL_COMPRESSED_RGB_565_VQ_TWID_KOS;
}
} break;
case 2: {
if(mipmapped) {
image->internalFormat = GL_COMPRESSED_ARGB_4444_VQ_MIPMAP_TWID_KOS;
} else {
image->internalFormat = GL_COMPRESSED_ARGB_4444_VQ_TWID_KOS;
}
}
break;
default:
fprintf(stderr, "Invalid texture format");
return 0;
}
} else {
switch(format) {
case 0: {
if(mipmapped) {
image->internalFormat = GL_COMPRESSED_ARGB_1555_VQ_MIPMAP_KOS;
} else {
image->internalFormat = GL_COMPRESSED_ARGB_1555_VQ_KOS;
}
} break;
case 1: {
if(mipmapped) {
image->internalFormat = GL_COMPRESSED_RGB_565_VQ_MIPMAP_KOS;
} else {
image->internalFormat = GL_COMPRESSED_RGB_565_VQ_KOS;
}
} break;
case 2: {
if(mipmapped) {
image->internalFormat = GL_COMPRESSED_ARGB_4444_VQ_MIPMAP_KOS;
} else {
image->internalFormat = GL_COMPRESSED_ARGB_4444_VQ_KOS;
}
}
break;
default:
fprintf(stderr, "Invalid texture format");
return 0;
}
}
} else {
printf("Not a compressed texture");
return 0;
}
// we're done.
return 1;
}
// Load Bitmaps And Convert To Textures
void LoadGLTextures() {
// Load Texture
Image *image1;
// allocate space for texture
image1 = (Image *) malloc(sizeof(Image));
if (image1 == NULL) {
printf("Error allocating space for image");
exit(0);
}
if (!ImageLoad("/rd/NeHe.tex", image1)) {
exit(1);
}
// Create Texture
glGenTextures(1, &texture[0]);
glBindTexture(GL_TEXTURE_2D, texture[0]); // 2d texture (x and y size)
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR); // scale linearly when image bigger than texture
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR); // scale linearly when image smalled than texture
// 2d texture, level of detail 0 (normal), 3 components (red, green, blue), x size from image, y size from image,
// border 0 (normal), rgb color data, unsigned byte data, and finally the data itself.
glCompressedTexImage2DARB(
GL_TEXTURE_2D, 0, image1->internalFormat, image1->sizeX, image1->sizeY, 0,
image1->dataSize, image1->data
);
free(image1);
};
/* A general OpenGL initialization function. Sets all of the initial parameters. */
void InitGL(int Width, int Height) // We call this right after our OpenGL window is created.
{
LoadGLTextures();
glEnable(GL_TEXTURE_2D);
glClearColor(0.0f, 0.0f, 0.0f, 0.0f); // This Will Clear The Background Color To Black
glClearDepth(1.0); // Enables Clearing Of The Depth Buffer
glDepthFunc(GL_LESS); // The Type Of Depth Test To Do
glEnable(GL_DEPTH_TEST); // Enables Depth Testing
glShadeModel(GL_SMOOTH); // Enables Smooth Color Shading
glMatrixMode(GL_PROJECTION);
glLoadIdentity(); // Reset The Projection Matrix
gluPerspective(45.0f,(GLfloat)Width/(GLfloat)Height,0.1f,100.0f); // Calculate The Aspect Ratio Of The Window
glMatrixMode(GL_MODELVIEW);
}
/* The function called when our window is resized (which shouldn't happen, because we're fullscreen) */
void ReSizeGLScene(int Width, int Height)
{
if (Height == 0) // Prevent A Divide By Zero If The Window Is Too Small
Height = 1;
glViewport(0, 0, Width, Height); // Reset The Current Viewport And Perspective Transformation
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(45.0f,(GLfloat)Width/(GLfloat)Height,0.1f,100.0f);
glMatrixMode(GL_MODELVIEW);
}
int check_start() {
#ifdef __DREAMCAST__
maple_device_t *cont;
cont_state_t *state;
cont = maple_enum_type(0, MAPLE_FUNC_CONTROLLER);
if(cont) {
state = (cont_state_t *)maple_dev_status(cont);
if(state)
return state->buttons & CONT_START;
}
#endif
return 0;
}
/* The main drawing function. */
void DrawGLScene()
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); // Clear The Screen And The Depth Buffer
glLoadIdentity(); // Reset The View
glTranslatef(0.0f,0.0f,-5.0f); // move 5 units into the screen.
glRotatef(xrot,1.0f,0.0f,0.0f); // Rotate On The X Axis
glRotatef(yrot,0.0f,1.0f,0.0f); // Rotate On The Y Axis
glRotatef(zrot,0.0f,0.0f,1.0f); // Rotate On The Z Axis
glBindTexture(GL_TEXTURE_2D, texture[0]); // choose the texture to use.
glBegin(GL_QUADS); // begin drawing a cube
// Front Face (note that the texture's corners have to match the quad's corners)
glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, -1.0f, 1.0f); // Bottom Left Of The Texture and Quad
glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, -1.0f, 1.0f); // Bottom Right Of The Texture and Quad
glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f, 1.0f, 1.0f); // Top Right Of The Texture and Quad
glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, 1.0f, 1.0f); // Top Left Of The Texture and Quad
// Back Face
glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f, -1.0f); // Bottom Right Of The Texture and Quad
glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f, 1.0f, -1.0f); // Top Right Of The Texture and Quad
glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f, 1.0f, -1.0f); // Top Left Of The Texture and Quad
glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f, -1.0f); // Bottom Left Of The Texture and Quad
// Top Face
glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, 1.0f, -1.0f); // Top Left Of The Texture and Quad
glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, 1.0f, 1.0f); // Bottom Left Of The Texture and Quad
glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, 1.0f, 1.0f); // Bottom Right Of The Texture and Quad
glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f, 1.0f, -1.0f); // Top Right Of The Texture and Quad
// Bottom Face
glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f, -1.0f, -1.0f); // Top Right Of The Texture and Quad
glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f, -1.0f, -1.0f); // Top Left Of The Texture and Quad
glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f, 1.0f); // Bottom Left Of The Texture and Quad
glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f, 1.0f); // Bottom Right Of The Texture and Quad
// Right face
glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, -1.0f, -1.0f); // Bottom Right Of The Texture and Quad
glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f, 1.0f, -1.0f); // Top Right Of The Texture and Quad
glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f, 1.0f, 1.0f); // Top Left Of The Texture and Quad
glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f, 1.0f); // Bottom Left Of The Texture and Quad
// Left Face
glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, -1.0f, -1.0f); // Bottom Left Of The Texture and Quad
glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f, 1.0f); // Bottom Right Of The Texture and Quad
glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f, 1.0f, 1.0f); // Top Right Of The Texture and Quad
glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, 1.0f, -1.0f); // Top Left Of The Texture and Quad
glEnd(); // done with the polygon.
xrot+=1.5f; // X Axis Rotation
yrot+=1.5f; // Y Axis Rotation
zrot+=1.5f; // Z Axis Rotation
//
// swap buffers to display, since we're double buffered.
glKosSwapBuffers();
}
int main(int argc, char **argv)
{
glKosInit();
InitGL(640, 480);
ReSizeGLScene(640, 480);
while(1) {
if(check_start())
break;
DrawGLScene();
}
return 0;
}