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a dinosaur
2024-05-29 01:10:53 +10:00
parent ce23f15169
commit 62062b4f7b
1 changed files with 88 additions and 91 deletions
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179
Lesson10.c
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@@ -1,19 +1,19 @@
/*
* This code was created by Lionel Brits & Jeff Molofee 2000.
* A HUGE thanks to Fredric Echols for cleaning up
* and optimizing the base code, making it more flexible!
* If you've found this code useful, please let me know.
* Visit my site at https://nehe.gamedev.net
* This code was created by Lionel Brits & Jeff Molofee 2000.
* A HUGE thanks to Fredric Echols for cleaning up
* and optimizing the base code, making it more flexible!
* If you've found this code useful, please let me know.
* Visit my site at https://nehe.gamedev.net
*/
#include <math.h> // Standard math library
#include <stdio.h> // Standard input/output
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <SDL3/SDL.h>
#define SDL_MAIN_USE_CALLBACKS
#include <SDL3/SDL_main.h>
#include <SDL3/SDL_opengl.h> // SDL wrapper header for the OpenGL library
#include <SDL3/SDL_opengl.h>
#define BTTN_YES 0
#define BTTN_NO 1
@@ -47,10 +47,10 @@ typedef struct tagCAMERA
{
float heading;
float xpos, zpos;
float yrot; // Y rotation
float yrot;
float walkbias, walkbiasangle;
float lookupdown;
float z; // Depth into the screen
float z;
} CAMERA;
typedef struct tagVERTEX
@@ -72,16 +72,16 @@ typedef struct tagSECTOR
typedef struct tagAPPSTATE
{
SDL_Window *win; // Holds our window handle
SDL_GLContext ctx; // OpenGL rendering context
SDL_Window *win;
SDL_GLContext ctx;
bool fullscreen, blend;
CAMERA camera;
unsigned filter; // Which filter to use
GLuint texture[3]; // Storage for 3 textures
unsigned filter; // Filtered texture selection
GLuint texture[3]; // Filtered textures
SECTOR sector1; // Our model goes here
SECTOR sector1;
} APPSTATE;
static void readstr(FILE *f, char *string)
@@ -153,11 +153,11 @@ static bool FlipSurface(SDL_Surface *surface)
return true;
}
static bool LoadGLTextures(APPSTATE *state) // Load bitmap as textures
static bool LoadGLTextures(APPSTATE *state)
{
SDL_Surface *TextureImage = NULL; // Create storage space for the texture
SDL_Surface *TextureImage = NULL;
// Load & flip the bitmap, check for errors
// Load & flip the bitmap
if (!(TextureImage = SDL_LoadBMP("Data/Mud.bmp")) || !FlipSurface(TextureImage))
{
return false;
@@ -181,7 +181,8 @@ static bool LoadGLTextures(APPSTATE *state) // Load bitmap
0, GL_BGR, GL_UNSIGNED_BYTE, TextureImage->pixels);
}
SDL_DestroySurface(TextureImage); // Free the image structure
// Free temporary surface
SDL_DestroySurface(TextureImage);
return true;
}
@@ -202,50 +203,53 @@ static void gluPerspective(GLdouble fovy, GLdouble aspect, GLdouble zNear, GLdou
glLoadMatrixd(mtx);
}
static void ReSizeGLScene(int width, int height) // Resize and initialize the OpenGL window
/* Set viewport size and setup matrices *
* width - Width of the OpenGL framebuffer *
* height - Height of the OpenGL framebuffer */
static void ReSizeGLScene(int width, int height)
{
if (height == 0) // Prevent division by zero by making height non-zero
if (height == 0) // Prevent division-by-zero by ensuring height is non-zero
{
height = 1;
}
glViewport(0, 0, width, height); // Reset the current viewport
glViewport(0, 0, width, height); // Reset the current viewport
glMatrixMode(GL_PROJECTION); // Select the projection matrix
glLoadIdentity(); // Reset the projection matrix
glMatrixMode(GL_PROJECTION); // Select & reset the projection matrix
glLoadIdentity();
// Calculate The Aspect Ratio Of The Window
gluPerspective(45.0f, (float)width / (float)height, 0.1f, 100.0f);
float aspect = (float)width / (float)height; // Calculate aspect ratio
gluPerspective(45.0f, aspect, 0.1f, 100.0f); // Setup perspective matrix
glMatrixMode(GL_MODELVIEW); // Select the modelview matrix
glLoadIdentity(); // Reset the modelview matrix
glMatrixMode(GL_MODELVIEW); // Select & reset the modelview matrix
glLoadIdentity();
}
static bool InitGL(APPSTATE *state) // All setup for OpenGL goes here
static bool InitGL(APPSTATE *state)
{
if (!LoadGLTextures(state)) // Call texture loading function
if (!LoadGLTextures(state)) // Load textures
{
return false;
}
glEnable(GL_TEXTURE_2D); // Enable texture mapping
glBlendFunc(GL_SRC_ALPHA, GL_ONE); // Set the blending function for translucency
glClearColor(0.0f, 0.0f, 0.0f, 0.0f); // Set the background clear color to black
glClearDepth(1.0); // Ensure depth buffer clears to furthest value
glDepthFunc(GL_LESS); // Pass if pixel depth value tests less than the depth buffer value
glEnable(GL_DEPTH_TEST); // Enable depth testing
glShadeModel(GL_SMOOTH); // Enable Smooth color shading
glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST); // Request the implementation to use perspective correct interpolation
glEnable(GL_TEXTURE_2D); // Enable texture mapping
glBlendFunc(GL_SRC_ALPHA, GL_ONE); // Set the blending function for translucency
glClearColor(0.0f, 0.0f, 0.0f, 0.0f); // Set the background clear color to black
glClearDepth(1.0); // Ensure depth buffer clears to furthest value
glDepthFunc(GL_LESS); // Pass if pixel depth value tests less than the depth buffer value
glEnable(GL_DEPTH_TEST); // Enable depth testing
glShadeModel(GL_SMOOTH); // Enable Smooth color shading
glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST); // Request the implementation to use perspective correct interpolation
SetupWorld(state);
return true; // Initialization went OK
return true;
}
static void DrawGLScene(APPSTATE *state) // Here's where we do all the drawing
static void DrawGLScene(APPSTATE *state)
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); // Clear the screen and the depth buffer
glLoadIdentity(); // Reset the view
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); // Clear the color and depth buffers
glLoadIdentity(); // Reset modelview
GLfloat x_m, y_m, z_m, u_m, v_m;
GLfloat xtrans = -state->camera.xpos;
@@ -263,7 +267,6 @@ static void DrawGLScene(APPSTATE *state) // Here's where we do a
numtriangles = state->sector1.numtriangles;
// Process Each Triangle
for (int loop_m = 0; loop_m < numtriangles; loop_m++)
{
glBegin(GL_TRIANGLES);
@@ -292,27 +295,29 @@ static void DrawGLScene(APPSTATE *state) // Here's where we do a
}
}
static void KillGLWindow(APPSTATE *state) // Properly kill the window
static void KillGLWindow(APPSTATE *state)
{
if (state->fullscreen) // Are we in fullscreen mode?
// Restore windowed state & cursor visibility
if (state->fullscreen)
{
SDL_SetWindowFullscreen(state->win, SDL_FALSE); // If so switch back to the desktop
SDL_ShowCursor(); // Show mouse pointer
SDL_SetWindowFullscreen(state->win, SDL_FALSE);
SDL_ShowCursor();
}
if (state->ctx) // Do we have a rendering context?
// Release and delete rendering context
if (state->ctx)
{
if (SDL_GL_MakeCurrent(state->win, NULL)) // Are we able to release the DC and RC contexts?
if (SDL_GL_MakeCurrent(state->win, NULL))
{
SDL_ShowSimpleMessageBox(SDL_MESSAGEBOX_INFORMATION, "SHUTDOWN ERROR", "Release Of RC Failed.", NULL);
}
SDL_GL_DeleteContext(state->ctx); // Delete the RC
state->ctx = NULL; // Set RC to NULL
SDL_GL_DeleteContext(state->ctx);
state->ctx = NULL;
}
SDL_DestroyWindow(state->win); // Destroy the window
state->win = NULL; // Set hWnd to NULL
SDL_DestroyWindow(state->win);
state->win = NULL;
}
@@ -324,36 +329,28 @@ static void KillGLWindow(APPSTATE *state) // Properly kill the wi
* fullscreenflag - Use fullscreen mode (true) Or windowed mode (false) */
static bool CreateGLWindow(APPSTATE *state, char *title, int width, int height, int bits, bool fullscreenflag)
{
SDL_Rect WindowRect; // Grabs rectangle upper left / lower right values
WindowRect.x = 0; // Set left value to 0
WindowRect.w = width; // Set right value to requested width
WindowRect.y = 0; // Set top value to 0
WindowRect.h = height; // Set bottom value to requested height
state->fullscreen = fullscreenflag;
state->fullscreen = fullscreenflag; // Set the fullscreen flag
// Create The Window
if (!(state->win = SDL_CreateWindow(title,
WindowRect.w, // Window width
WindowRect.h, // Window height
if (!(state->win = SDL_CreateWindow(title, width, height,
SDL_WINDOW_HIDDEN | SDL_WINDOW_OPENGL | SDL_WINDOW_RESIZABLE | SDL_WINDOW_HIGH_PIXEL_DENSITY)))
{
SDL_ShowSimpleMessageBox(SDL_MESSAGEBOX_ERROR, "ERROR", "Window Creation Error.", NULL);
return false; // Return false
return false;
}
if (fullscreenflag) // Attempt fullscreen mode?
// Try entering fullscreen mode if requested
if (fullscreenflag)
{
if (SDL_SetWindowFullscreen(state->win, SDL_TRUE) < 0) // Try to set selected mode and get results
if (SDL_SetWindowFullscreen(state->win, SDL_TRUE) < 0)
{
// If mode switching fails, ask the user to quit or use to windowed mode
int bttnid = ShowYesNoMessageBox(state->win, BTTN_YES, "NeHe GL",
"The Requested Fullscreen Mode Is Not Supported By\nYour Video Card. Use Windowed Mode Instead?");
if (bttnid == BTTN_NO)
{
// Show a meessage box letting the user know the program is closing
// User chose to quit
SDL_ShowSimpleMessageBox(SDL_MESSAGEBOX_WARNING, "ERROR", "Program Will Now Close.", NULL);
return false; // Return false
return false;
}
state->fullscreen = false;
}
@@ -362,42 +359,42 @@ static bool CreateGLWindow(APPSTATE *state, char *title, int width, int height,
SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_COMPATIBILITY);
SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 1);
SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 4);
SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1); // Must support double buffering
SDL_GL_SetAttribute(SDL_GL_RED_SIZE, 0); // Color bits ignored
SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1); // Double buffered framebuffer
SDL_GL_SetAttribute(SDL_GL_RED_SIZE, 0); // Color bits ignored
SDL_GL_SetAttribute(SDL_GL_GREEN_SIZE, 0);
SDL_GL_SetAttribute(SDL_GL_BLUE_SIZE, 0);
SDL_GL_SetAttribute(SDL_GL_ALPHA_SIZE, 0); // No alpha buffer
SDL_GL_SetAttribute(SDL_GL_ACCUM_ALPHA_SIZE, 0); // No accumulation buffer
SDL_GL_SetAttribute(SDL_GL_ACCUM_RED_SIZE, 0); // Accumulation bits ignored
SDL_GL_SetAttribute(SDL_GL_ALPHA_SIZE, 0); // No alpha buffer
SDL_GL_SetAttribute(SDL_GL_ACCUM_ALPHA_SIZE, 0); // No accumulation buffer
SDL_GL_SetAttribute(SDL_GL_ACCUM_RED_SIZE, 0); // Accumulation bits ignored
SDL_GL_SetAttribute(SDL_GL_ACCUM_GREEN_SIZE, 0);
SDL_GL_SetAttribute(SDL_GL_ACCUM_BLUE_SIZE, 0);
SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 16); // 16-bit Z-buffer (depth buffer)
SDL_GL_SetAttribute(SDL_GL_STENCIL_SIZE, 0); // No stencil buffer
SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 16); // 16-bit Z-buffer (depth buffer)
SDL_GL_SetAttribute(SDL_GL_STENCIL_SIZE, 0); // No stencil buffer
if (!(state->ctx = SDL_GL_CreateContext(state->win))) // Are we able to get a rendering context?
if (!(state->ctx = SDL_GL_CreateContext(state->win))) // Create rendering context
{
SDL_ShowSimpleMessageBox(SDL_MESSAGEBOX_ERROR, "ERROR", "Can't Create A GL Rendering Context.", NULL);
return false; // Return false
return false;
}
if (SDL_GL_MakeCurrent(state->win, state->ctx)) // Try to activate the rendering context
if (SDL_GL_MakeCurrent(state->win, state->ctx)) // Activate the rendering context
{
SDL_ShowSimpleMessageBox(SDL_MESSAGEBOX_ERROR, "ERROR", "Can't Activate The GL Rendering Context.", NULL);
return false; // Return false
return false;
}
SDL_ShowWindow(state->win);
SDL_GL_SetSwapInterval(1);
ReSizeGLScene(width, height); // Set up our perspective OpenGL screen
SDL_GL_SetSwapInterval(1); // Enable VSync
ReSizeGLScene(width, height); // Set up our viewport and perspective
if (!InitGL(state)) // Initialize our newly created OpenGL window
if (!InitGL(state)) // Initialize the scene
{
SDL_ShowSimpleMessageBox(SDL_MESSAGEBOX_ERROR, "ERROR", "Initialization Failed.", NULL);
return false; // Return false
return false;
}
return true; // Success
return true;
}
int SDL_AppEvent(void *appstate, const SDL_Event *event)
@@ -406,12 +403,12 @@ int SDL_AppEvent(void *appstate, const SDL_Event *event)
switch (event->type)
{
case SDL_EVENT_QUIT: // Have we received a quit event?
return SDL_APP_SUCCESS; // Exit with success status
return SDL_APP_SUCCESS;
case SDL_EVENT_KEY_DOWN:
if (event->key.keysym.sym == SDLK_ESCAPE) // Quit on escape key
{
return SDL_APP_SUCCESS; // Exit with success status
return SDL_APP_SUCCESS;
}
if (!event->key.repeat) // Was a key just pressed?
{
@@ -559,7 +556,7 @@ int SDL_AppInit(void **appstate, int argc, char *argv[])
.ctx = NULL,
.fullscreen = false,
.blend = false, // Blending off
.blend = false, // Blending off
.camera = (CAMERA)
{
@@ -586,7 +583,7 @@ int SDL_AppInit(void **appstate, int argc, char *argv[])
const bool wantfullscreen = (bttnid == BTTN_YES);
if (!CreateGLWindow(state, "Lionel Brits & NeHe's 3D World Tutorial", 640, 480, 16, wantfullscreen))
{
return SDL_APP_FAILURE; // Quit if window was not created
return SDL_APP_FAILURE;
}
return SDL_APP_CONTINUE;
@@ -594,7 +591,6 @@ int SDL_AppInit(void **appstate, int argc, char *argv[])
void SDL_AppQuit(void *appstate)
{
// Shutdown
if (appstate)
{
APPSTATE *state = (APPSTATE *)appstate;
@@ -603,8 +599,9 @@ void SDL_AppQuit(void *appstate)
{
glDeleteTextures(3, state->texture);
}
KillGLWindow(state); // Kill the window
KillGLWindow(state);
free(state);
}
SDL_Quit();
}