From 1e541ac7382e9cf96287ff2ec810d79623cc80be Mon Sep 17 00:00:00 2001
From: John Tsiombikas <nuclear@member.fsf.org>
Date: Sun, 20 Jun 2021 22:50:19 +0300
Subject: [PATCH] foo

---
 src/main.c |   63 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
 src/rt.c   |   37 +++++++++++++++++++++++++++++++++++
 src/rt.h   |   11 +++++++++++
 3 files changed, 110 insertions(+), 1 deletion(-)
 create mode 100644 src/rt.c

diff --git a/src/main.c b/src/main.c
index a831feb..72cc76c 100644
--- a/src/main.c
+++ b/src/main.c
@@ -42,7 +42,7 @@ static void skeydown(int key, int x, int y);
 static void skeyup(int key, int x, int y);
 static void mouse(int bn, int st, int x, int y);
 static void motion(int x, int y);
-
+static unsigned int nextpow2(unsigned int x);
 
 static long start_time;
 
@@ -65,6 +65,12 @@ static int keymap[NUM_INPUTS][2] = {
 
 static struct level lvl;
 
+static unsigned int tex;
+static int tex_width, tex_height;
+static int tex_intfmt;
+static float tex_xform[16];
+
+
 int main(int argc, char **argv)
 {
 	glutInit(&argc, argv);
@@ -96,9 +102,18 @@ static int init(void)
 {
 	glEnable(GL_CULL_FACE);
 
+	/*
 	glEnable(GL_DEPTH_TEST);
 	glEnable(GL_LIGHTING);
 	glEnable(GL_LIGHT0);
+	*/
+
+	glGenTextures(1, &tex);
+	glBindTexture(GL_TEXTURE_2D, tex);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+
+	tex_intfmt = GL_RGB16F;
 
 	if(load_level(&lvl, "data/test.lvl") == -1) {
 		return -1;
@@ -111,6 +126,8 @@ static int init(void)
 static void cleanup(void)
 {
 	destroy_level(&lvl);
+
+	glDeleteTextures(1, &tex);
 }
 
 #define WALK_SPEED 3.0f
@@ -152,12 +169,30 @@ static void display(void)
 {
 	update();
 
+	render();
+	glBindTexture(GL_TEXTURE_2D, tex);
+	glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, fb.width, fb.height, GL_RGB, GL_FLOAT, fb.pixels);
+	glEnable(GL_TEXTURE_2D);
+
+	glBegin(GL_QUADS);
+	glTexCoord2f(0, 0);
+	glVertex2f(-1, -1);
+	glTexCoord2f(1, 0);
+	glVertex2f(1, -1);
+	glTexCoord2f(1, 1);
+	glVertex2f(1, 1);
+	glTexCoord2f(0, 1);
+	glVertex2f(-1, 1);
+	glEnd();
+
+	/*
 	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 
 	glMatrixMode(GL_MODELVIEW);
 	glLoadMatrixf(pxform);
 
 	draw_level(&lvl);
+	*/
 
 	glutSwapBuffers();
 	assert(glGetError() == GL_NO_ERROR);
@@ -170,12 +205,27 @@ static void idle(void)
 
 static void reshape(int x, int y)
 {
+	/*
 	float proj[16];
 
 	cgm_mperspective(proj, cgm_deg_to_rad(50.0f), (float)x / (float)y, 0.5, 500.0);
 
 	glMatrixMode(GL_PROJECTION);
 	glLoadMatrixf(proj);
+	*/
+
+	if(x > tex_width || y > tex_height) {
+		tex_width = nextpow2(x);
+		tex_height = nextpow2(y);
+
+		glBindTexture(GL_TEXTURE_2D, tex);
+		glTexImage2D(GL_TEXTURE_2D, 0, tex_intfmt, tex_width, tex_height, 0, GL_RGB, GL_FLOAT, 0);
+	}
+	fbsize(x, y);
+	cgm_mscaling(tex_xform, (float)x / tex_width, (float)y / tex_height, 1.0f);
+
+	glMatrixMode(GL_TEXTURE);
+	glLoadMatrixf(tex_xform);
 }
 
 static void keyb(int key, int press)
@@ -234,3 +284,14 @@ static void motion(int x, int y)
 		if(cam_phi > M_PI) cam_phi = M_PI;
 	}
 }
+
+static unsigned int nextpow2(unsigned int x)
+{
+	x--;
+	x |= x >> 1;
+	x |= x >> 2;
+	x |= x >> 4;
+	x |= x >> 8;
+	x |= x >> 16;
+	return x + 1;
+}
diff --git a/src/rt.c b/src/rt.c
new file mode 100644
index 0000000..2c6ceaf
--- /dev/null
+++ b/src/rt.c
@@ -0,0 +1,37 @@
+#include "rt.h"
+
+struct framebuffer fb;
+
+int fbsize(int width, int height)
+{
+	void *tmp;
+
+	if(!(tmp = malloc(width * height * sizeof *fb.pixels))) {
+		return -1;
+	}
+
+	free(fb.pixels);
+	fb.pixels = tmp;
+	fb.width = width;
+	fb.height = height;
+	return 0;
+}
+
+void render(void)
+{
+	int i, j;
+	cgm_vec3 *fbptr = fb.pixels;
+
+	for(i=0; i<fb.height; i++) {
+		for(j=0; j<fb.width; j++) {
+			if(i < 3 || i >= fb.height - 3 || j < 3 || j >= fb.width - 3) {
+				fbptr->x = 1.0f;
+				fbptr->y = fbptr->z = 0.0f;
+			} else {
+				fbptr->x = fbptr->z = 0.0f;
+				fbptr->y = 1.0f;
+			}
+			fbptr++;
+		}
+	}
+}
diff --git a/src/rt.h b/src/rt.h
index 7f09375..b06fd64 100644
--- a/src/rt.h
+++ b/src/rt.h
@@ -12,4 +12,15 @@ struct material {
 	struct image *tex_color;
 };
 
+struct framebuffer {
+	int width, height;
+	cgm_vec3 *pixels;
+};
+
+extern struct framebuffer fb;
+
+int fbsize(int width, int height);
+
+void render(void);
+
 #endif	/* RT_H_ */
-- 
1.7.10.4