X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?a=blobdiff_plain;f=src%2Fpost.cc;fp=src%2Fpost.cc;h=b675f5b77c127b788e52de4c11136d0af53922dc;hb=3aacec4aee795e703e8eb9d6852ca47a3be065ee;hp=0000000000000000000000000000000000000000;hpb=c5c29f4044110dd153ee5ca3b018c812d518a053;p=laserbrain_demo

diff --git a/src/post.cc b/src/post.cc
new file mode 100644
index 0000000..b675f5b
--- /dev/null
+++ b/src/post.cc
@@ -0,0 +1,67 @@
+#include "opengl.h"
+#include "app.h"
+
+static void update_fbtex();
+
+static unsigned int fb_tex;
+static int fb_tex_width, fb_tex_height;
+
+void slow_post(unsigned int sdr)
+{
+	update_fbtex();
+
+	glBindTexture(GL_TEXTURE_2D, fb_tex);
+	glCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 0, 0, win_width, win_height);
+
+	glPushAttrib(GL_ENABLE_BIT);
+	glDisable(GL_DEPTH_TEST);
+	glDisable(GL_LIGHTING);
+
+	glUseProgram(sdr);
+
+	float umax = (float)win_width / (float)fb_tex_width;
+	float vmax = (float)win_height / (float)fb_tex_height;
+
+	glBegin(GL_QUADS);
+	glTexCoord2f(0, 0);
+	glVertex2f(-1, -1);
+	glTexCoord2f(umax, 0);
+	glVertex2f(1, -1);
+	glTexCoord2f(umax, vmax);
+	glVertex2f(1, 1);
+	glTexCoord2f(0, vmax);
+	glVertex2f(-1, 1);
+	glEnd();
+
+	glPopAttrib();
+}
+
+static int next_pow2(int x)
+{
+	x--;
+	x = (x >> 1) | x;
+	x = (x >> 2) | x;
+	x = (x >> 4) | x;
+	x = (x >> 8) | x;
+	x = (x >> 16) | x;
+	return x + 1;
+}
+
+static void update_fbtex()
+{
+	if(win_width <= fb_tex_width && win_height <= fb_tex_height) {
+		return;		// nothing to do
+	}
+	if(!fb_tex) {
+		glGenTextures(1, &fb_tex);
+		glBindTexture(GL_TEXTURE_2D, fb_tex);
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+	} else {
+		glBindTexture(GL_TEXTURE_2D, fb_tex);
+	}
+
+	fb_tex_width = next_pow2(win_width);
+	fb_tex_height = next_pow2(win_height);
+	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, fb_tex_width, fb_tex_height, 0, GL_RGB, GL_UNSIGNED_BYTE, 0);
+}