Initial import. First working main loop.

Switching from scene to scene is done.
Loading image to SDL, download SDL texture from VRAM to RAM is done.
caca background from SDL texture is "done".
GL drawing is not yet tried. Considering OpenGL3 + shaders.

8 files changed, 421 insertions, 0 deletions

diff --git a/src/main.c b/src/main.c
new file mode 100644
index 0000000..a73bf44
--- /dev/null
+++ b/src/main.c
@@ -0,0 +1,198 @@
+/*
+ * demoscene-eo, an ASCII art demoscene written as a gift for Emmanuel Otton retirement 
+ * Copyright (C) 2019  Ludovic Pouzenc <ludovic@pouzenc.fr>
+ *  
+ * This file is part of demoscene-eo.
+ *
+ *  demoscene-eo is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  demoscene-eo is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with demoscene-eo.  If not, see <http://www.gnu.org/licenses/>
+ */
+#include "main.h"
+#include "scene00.h"
+#include "scene01.h"
+#include "scene02.h"
+#define SCENE_COUNT 3
+#define SCENE_NEXT do { scene = (scene+1)%SCENE_COUNT; } while(0)
+
+#define EXPR_MIN_SIZE ( ge.w<80 || ge.h<25 )
+#define TEXT_MIN_SIZE "80x25"
+
+int main(void)
+{
+	int done=0, lastscene=-1, scene=0, paused=0, res;
+	Uint32 sdl_win_flags = SDL_WINDOW_OPENGL;
+	graphical_env_t ge;
+	scene00_env_t s00e;
+	scene01_env_t s01e;
+	scene02_env_t s02e;
+
+	caca_event_t caca_ev;
+	SDL_RendererInfo renderer_info;
+	SDL_Event sdl_ev;
+
+	// Initialize libcaca (http://caca.zoy.org/doxygen/libcaca/caca_8h.html)
+	ge.dp = caca_create_display(NULL);
+	if(!ge.dp) return 1;
+	caca_set_display_title(ge.dp, "demoscene-eo");
+	caca_set_display_time(ge.dp, 16666); // 1e6µs/60 = 16666.66... It is ~60 fps
+	ge.cv = caca_get_canvas(ge.dp);
+
+	ge.d = caca_create_dither(32, 256, 256, 256*4, 0x00ff0000, 0x0000ff00, 0x000000ff, 0);
+	if ( !ge.d ) return 2;
+	caca_set_dither_color(ge.d, "16");
+
+	// Initialize SDL (http://wiki.libsdl.org/SDL_CreateWindowAndRenderer)
+	// Useful snippet : https://gist.github.com/koute/7391344
+	res = SDL_Init(SDL_INIT_VIDEO);
+	if ( res == -1) return 3;
+	SDL_GL_SetAttribute( SDL_GL_DOUBLEBUFFER, 1 );
+	SDL_GL_SetAttribute( SDL_GL_ACCELERATED_VISUAL, 1 );
+	SDL_GL_SetAttribute( SDL_GL_RED_SIZE, 8 );
+	SDL_GL_SetAttribute( SDL_GL_GREEN_SIZE, 8 );
+	SDL_GL_SetAttribute( SDL_GL_BLUE_SIZE, 8 );
+	SDL_GL_SetAttribute( SDL_GL_ALPHA_SIZE, 8 );
+	SDL_GL_SetAttribute( SDL_GL_CONTEXT_MAJOR_VERSION, 3 );
+	SDL_GL_SetAttribute( SDL_GL_CONTEXT_MINOR_VERSION, 2 );
+	SDL_GL_SetAttribute( SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_CORE );	
+
+	//XXX for final version, consider sdl_win_flags |= SDL_WINDOW_HIDDEN;
+	res = SDL_CreateWindowAndRenderer(256, 256, sdl_win_flags, &ge.sdl_win, &ge.sdl_rndr);
+	if ( res == -1) return 4;
+	SDL_SetWindowTitle(ge.sdl_win, "SDL/GL debug");
+	res = SDL_GetRendererInfo(ge.sdl_rndr, &renderer_info);
+	if ( res < 0 ) return 5;
+	if ( !(renderer_info.flags & SDL_RENDERER_ACCELERATED)) return 6;
+	if ( !(renderer_info.flags & SDL_RENDERER_TARGETTEXTURE)) return 7;
+	ge.sdl_target = SDL_CreateTexture(ge.sdl_rndr, SDL_PIXELFORMAT_RGBA8888, SDL_TEXTUREACCESS_TARGET, 256, 256);
+	if ( ge.sdl_target == NULL ) return 9;
+	ge.raw_target = malloc(256*256*4);
+	if ( ge.raw_target == NULL ) return 10;
+	ge.gl_ctx = SDL_GL_CreateContext(ge.sdl_win);
+	if ( ge.gl_ctx == NULL ) return 11;
+
+	
+	// Initialize OpenGL
+	glShadeModel(GL_SMOOTH);
+	glClearDepth(1.0f);
+	glEnable(GL_DEPTH_TEST);
+	glDepthFunc(GL_LEQUAL);
+	glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
+	glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);
+
+	glDisable(GL_TEXTURE_2D);
+	glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+	glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+	glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
+	glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
+	glEnable(GL_CULL_FACE);
+	glCullFace(GL_FRONT);
+	glViewport(0, 0, (GLsizei)256, (GLsizei)256);
+	glMatrixMode(GL_PROJECTION); glLoadIdentity(); gluPerspective(45.0f, 1.0f, 0.1f, 100.0f); // 1.0f==ratio
+	glMatrixMode(GL_MODELVIEW);  glLoadIdentity();
+
+	// Main libcaca loop for caca window (OpenGL could be used in sceneN_next())
+	ge.framecount=0;
+	do {
+		// Check canvas size at every frame because of unreliable CACA_EVENT_RESIZE
+		ge.w = caca_get_canvas_width(ge.cv);
+		ge.h = caca_get_canvas_height(ge.cv);
+		if ( EXPR_MIN_SIZE ) {
+			caca_set_color_ansi(ge.cv, CACA_BLACK, CACA_WHITE);
+			caca_put_str(ge.cv, 0, 0, "Need a minimum of " TEXT_MIN_SIZE " terminal");
+		} else if (!paused) {
+			// init / free if scene transition
+			if ( lastscene != scene ) {
+				switch(lastscene) {
+					case 0: scene00_free(&ge, &s00e); break;
+					case 1: scene01_free(&ge, &s01e); break;
+					case 2: scene02_free(&ge, &s02e); break;
+				}
+			}
+			while ( lastscene != scene ) {
+				ge.sdl_ticks = SDL_GetTicks();
+				ge.sc_framecount = 0;
+				switch(scene) {
+					case 0: res = scene00_init(&ge, &s00e); break;
+					case 1: res = scene01_init(&ge, &s01e); break;
+					case 2: res = scene02_init(&ge, &s02e); break;
+				}
+				// If scene init fail, skip to the next one
+				if (res) SCENE_NEXT; else lastscene = scene;
+			}
+			// Compute current scene0 frame
+			ge.sdl_ticks = SDL_GetTicks(); // This value wraps if the program runs for more than ~49 days
+			switch(scene) {
+				case 0: res = scene00_next(&ge, &s00e); break;
+				case 1: res = scene01_next(&ge, &s01e); break;
+				case 2: res = scene02_next(&ge, &s02e); break;
+			}
+			if (res) SCENE_NEXT;
+			ge.framecount++;
+			ge.sc_framecount++;
+		}
+		// Display it
+		caca_refresh_display(ge.dp); // Auto framerate limiting (see caca_set_display_time())
+
+		// Event handling for the libcaca "window" (depending on CACA_DRIVER env variable)
+		if ( caca_get_event(ge.dp, CACA_EVENT_KEY_PRESS|CACA_EVENT_RESIZE|CACA_EVENT_QUIT, &caca_ev, 0) ) {
+			switch(caca_get_event_type(&caca_ev)) {
+					case CACA_EVENT_QUIT:
+						done = 1;
+						break;
+					case CACA_EVENT_KEY_PRESS:
+						switch(caca_get_event_key_ch(&caca_ev)) {
+							case 'q': done = 1; break;
+							case 'p': paused = !paused; break;
+							case CACA_KEY_ESCAPE: SCENE_NEXT; break;
+						}
+						break;
+						/* On Debian 10, no CACA_EVENT_RESIZE when using x11 CACA_DRIVER
+					case CACA_EVENT_RESIZE:
+						w = caca_get_event_resize_width(&caca_ev);
+						h = caca_get_event_resize_height(&caca_ev);
+						small = EXPR_MIN_SIZE;
+						break;
+						*/
+					default:
+						break;
+			}
+		}
+		// Event handling for the SDL/GL window (debug purposes)
+		while(SDL_PollEvent(&sdl_ev)) {
+			switch(sdl_ev.type) {
+				case SDL_QUIT:
+					done = 1;
+					break;
+				case SDL_KEYDOWN:
+					switch(sdl_ev.key.keysym.sym) {
+						case SDLK_q: done = 1; break;
+						case SDLK_p: paused = !paused; break;
+						case SDLK_ESCAPE: SCENE_NEXT; break;
+					}
+					break;
+				default:
+					break;
+			}
+		}
+	} while(!done);
+
+	caca_free_dither(ge.d);
+	caca_free_display(ge.dp);
+	ge.cv=NULL;
+	SDL_GL_DeleteContext(ge.gl_ctx);
+	SDL_DestroyTexture(ge.sdl_target);
+	SDL_DestroyRenderer(ge.sdl_rndr);
+	SDL_DestroyWindow(ge.sdl_win);
+	SDL_Quit();
+	return 0;
+}
diff --git a/src/main.h b/src/main.h
new file mode 100644
index 0000000..b2b0a6e
--- /dev/null
+++ b/src/main.h
@@ -0,0 +1,23 @@
+#ifndef MAIN_H_INCLUDED
+#define MAIN_H_INCLUDED
+
+#include <caca.h>
+#include <SDL2/SDL.h>
+#include <SDL2/SDL_opengl.h>
+#include <GL/glu.h>
+
+typedef struct {
+	caca_display_t *dp;
+	caca_canvas_t *cv;
+   	caca_dither_t *d;
+	int w, h; // caca terminal size in characters
+	SDL_Window* sdl_win;
+	SDL_Renderer *sdl_rndr;
+	SDL_Texture *sdl_target;
+	void *raw_target;
+	SDL_GLContext gl_ctx;
+	Uint32 sdl_ticks;
+	Uint32 framecount;
+	Uint32 sc_framecount;
+} graphical_env_t;
+#endif
diff --git a/src/scene00.c b/src/scene00.c
new file mode 100644
index 0000000..746db29
--- /dev/null
+++ b/src/scene00.c
@@ -0,0 +1,73 @@
+/*
+ * demoscene-eo, an ASCII art demoscene written as a gift for Emmanuel Otton retirement 
+ * Copyright (C) 2019  XXXXXX XXXXXXX <xxxxxx@xxxxxx.fr>
+ *  
+ * This file is part of demoscene-eo.
+ *
+ *  demoscene-eo is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  demoscene-eo is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with demoscene-eo.  If not, see <http://www.gnu.org/licenses/>
+ */
+#include "scene00.h"
+
+int scene00_init(graphical_env_t *ge, scene00_env_t *se) {
+	SDL_Surface *bmpSurf = SDL_LoadBMP("./res/eo1.bmp");
+	se->eo1 = SDL_CreateTextureFromSurface(ge->sdl_rndr, bmpSurf);
+	SDL_FreeSurface(bmpSurf);
+
+	return 0;
+}
+
+void scene00_free(graphical_env_t *ge, scene00_env_t *se) {
+	SDL_DestroyTexture(se->eo1); se->eo1=NULL;
+}
+
+int scene00_next(graphical_env_t *ge, scene00_env_t *se) {
+	// Shorthands
+	caca_canvas_t *cv = ge->cv;
+	int w = ge->w, h = ge->h;
+	Uint32 frame = ge->sc_framecount;
+	SDL_Renderer *r = ge->sdl_rndr;
+	// Local vars
+	int res;
+
+	// https://gist.github.com/Twinklebear/8265888
+	// https://forums.libsdl.org/viewtopic.php?p=51634
+
+	// Render all the stuff on target texture
+	SDL_SetRenderTarget(r, ge->sdl_target);
+	SDL_RenderCopy(r, se->eo1, NULL, NULL);
+	// [...]
+
+	// Copy the SDL screen to SDL debug window (and display it, not mandatory)
+	SDL_SetRenderTarget(r, NULL);
+	SDL_RenderCopy(r, ge->sdl_target, NULL, NULL);
+	SDL_RenderPresent(r);
+	
+	// Download the rendered texture from videocard to main memory
+	res = SDL_RenderReadPixels(r, NULL, 0, ge->raw_target, 256*4);
+
+	// "convert" the raw pixel stream to ASCII art on caca canevas
+	if ( res == 0 ) caca_dither_bitmap(cv, 0, 0, w, h, ge->d, ge->raw_target);
+
+	// Add things on top of caca canvas
+	caca_set_color_ansi(cv, CACA_BLACK, CACA_WHITE);
+	caca_put_str(cv, (w-17)/2, h/2, "This is a message");
+	caca_draw_line(cv,6,6,w-14,11, '*');
+	caca_draw_thin_line(cv,frame%10,frame%10,w-10+frame%10,h-10+frame%10);
+
+	if ( frame >= 100 ) {
+		return 1;
+	}
+	return 0;
+}
+
diff --git a/src/scene00.h b/src/scene00.h
new file mode 100644
index 0000000..b1c9d9d
--- /dev/null
+++ b/src/scene00.h
@@ -0,0 +1,12 @@
+#ifndef SCENE00_H_INCLUDED
+#define SCENE00_H_INCLUDED
+
+#include "main.h"
+typedef struct {
+	SDL_Texture *eo1;
+} scene00_env_t;
+
+int scene00_init(graphical_env_t *ge, scene00_env_t *se);
+void scene00_free(graphical_env_t *ge, scene00_env_t *se);
+int scene00_next(graphical_env_t *ge, scene00_env_t *se);
+#endif
diff --git a/src/scene01.c b/src/scene01.c
new file mode 100644
index 0000000..2b3e9f5
--- /dev/null
+++ b/src/scene01.c
@@ -0,0 +1,49 @@
+/*
+ * demoscene-eo, an ASCII art demoscene written as a gift for Emmanuel Otton retirement 
+ * Copyright (C) 2019  XXXXXX XXXXXXX <xxxxxx@xxxxxx.fr>
+ *  
+ * This file is part of demoscene-eo.
+ *
+ *  demoscene-eo is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  demoscene-eo is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with demoscene-eo.  If not, see <http://www.gnu.org/licenses/>
+ */
+#include "scene01.h"
+
+int scene01_init(graphical_env_t *ge, scene01_env_t *se) {
+	return 0;
+}
+
+void scene01_free(graphical_env_t *ge, scene01_env_t *se) {
+}
+
+int scene01_next(graphical_env_t *ge, scene01_env_t *se) {
+	// Shorthands
+	caca_canvas_t *cv = ge->cv;
+	int w = ge->w, h = ge->h;
+	Uint32 frame = ge->sc_framecount;
+
+	//XXX remove me
+	((Uint32 *)ge->raw_target)[frame%(256*256)]=frame<<((frame%3)*8);
+
+	caca_clear_canvas(cv);
+	caca_set_dither_gamma(ge->d, (100-frame%100)/100.0);
+	caca_dither_bitmap(cv, 0, 0, w, h, ge->d, ge->raw_target);
+
+	caca_set_color_ansi(cv, CACA_WHITE, CACA_BLACK);
+	caca_put_str(cv, (w-17)/2, h/2, "This is a message");
+
+	if ( frame >= 300 ) {
+		return 1;
+	}
+	return 0;
+}
diff --git a/src/scene01.h b/src/scene01.h
new file mode 100644
index 0000000..1f22de7
--- /dev/null
+++ b/src/scene01.h
@@ -0,0 +1,12 @@
+#ifndef SCENE01_H_INCLUDED
+#define SCENE01_H_INCLUDED
+
+#include "main.h"
+typedef struct {
+
+} scene01_env_t;
+
+int scene01_init(graphical_env_t *ge, scene01_env_t *se);
+void scene01_free(graphical_env_t *ge, scene01_env_t *se);
+int scene01_next(graphical_env_t *ge, scene01_env_t *se);
+#endif
diff --git a/src/scene02.c b/src/scene02.c
new file mode 100644
index 0000000..1989bf0
--- /dev/null
+++ b/src/scene02.c
@@ -0,0 +1,42 @@
+/*
+ * demoscene-eo, an ASCII art demoscene written as a gift for Emmanuel Otton retirement 
+ * Copyright (C) 2019  XXXXXX XXXXXXX <xxxxxx@xxxxxx.fr>
+ *  
+ * This file is part of demoscene-eo.
+ *
+ *  demoscene-eo is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  demoscene-eo is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with demoscene-eo.  If not, see <http://www.gnu.org/licenses/>
+ */
+#include "scene02.h"
+
+int scene02_init(graphical_env_t *ge, scene02_env_t *se) {
+	return 0;
+}
+
+void scene02_free(graphical_env_t *ge, scene02_env_t *se) {
+}
+
+int scene02_next(graphical_env_t *ge, scene02_env_t *se) {
+	// Shorthands
+	caca_canvas_t *cv = ge->cv;
+	//int w = ge->w, h = ge->h;
+	Uint32 frame = ge->sc_framecount;
+
+	caca_clear_canvas(cv);
+
+	if ( frame >= 100 ) {
+		return 1;
+	}
+	return 0;
+}
+
diff --git a/src/scene02.h b/src/scene02.h
new file mode 100644
index 0000000..49abbfb
--- /dev/null
+++ b/src/scene02.h
@@ -0,0 +1,12 @@
+#ifndef SCENE02_H_INCLUDED
+#define SCENE02_H_INCLUDED
+
+#include "main.h"
+typedef struct {
+
+} scene02_env_t;
+
+int scene02_init(graphical_env_t *ge, scene02_env_t *se);
+void scene02_free(graphical_env_t *ge, scene02_env_t *se);
+int scene02_next(graphical_env_t *ge, scene02_env_t *se);
+#endif