X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?p=antikythera;a=blobdiff_plain;f=src%2Fshadow.cc;fp=src%2Fshadow.cc;h=357ed8245e605a9b2afea34665cc71765c6c0200;hp=0000000000000000000000000000000000000000;hb=ccc1a688b59e25bb934a0d3e2bbf477960068d4f;hpb=080d7a779d43f549fc16c44e709cbf5989180fdf

diff --git a/src/shadow.cc b/src/shadow.cc
new file mode 100644
index 0000000..357ed82
--- /dev/null
+++ b/src/shadow.cc
@@ -0,0 +1,147 @@
+#define GPH_NAMESPACE
+#include <assert.h>
+#include "opengl.h"
+#include "shadow.h"
+#include "vmath/vmath.h"
+
+
+bool shadow_pass;
+
+static int tex_sz, prev_vp[4];
+static unsigned int fbo, depth_tex, rb_color;
+static gph::Mat4 shadow_mat;
+
+bool init_shadow(int sz)
+{
+	tex_sz = sz;
+	printf("initializing shadow buffer (%dx%d)\n", tex_sz, tex_sz);
+
+	glGenFramebuffers(1, &fbo);
+	glBindFramebuffer(GL_FRAMEBUFFER, fbo);
+
+	const float border_color[] = {1, 1, 1, 1};
+
+	glGenTextures(1, &depth_tex);
+	glBindTexture(GL_TEXTURE_2D, depth_tex);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_BORDER);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_BORDER);
+	glTexParameterfv(GL_TEXTURE_2D, GL_TEXTURE_BORDER_COLOR, border_color);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_MODE, GL_COMPARE_R_TO_TEXTURE);
+	glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT24, tex_sz, tex_sz, 0,
+			GL_DEPTH_COMPONENT, GL_UNSIGNED_BYTE, 0);
+	glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, depth_tex, 0);
+
+	assert(glGetError() == GL_NO_ERROR);
+
+	glDrawBuffer(GL_FALSE);
+	glReadBuffer(GL_FALSE);
+
+	if(glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE) {
+		fprintf(stderr, "incomplete framebuffer\n");
+		return false;
+	}
+
+	glBindFramebuffer(GL_FRAMEBUFFER, 0);
+	glDrawBuffer(GL_BACK);
+	glReadBuffer(GL_BACK);
+	assert(glGetError() == GL_NO_ERROR);
+
+	return true;
+}
+
+void destroy_shadow()
+{
+	glDeleteTextures(1, &depth_tex);
+	glDeleteRenderbuffers(1, &rb_color);
+	glDeleteFramebuffers(1, &fbo);
+}
+
+void begin_shadow_pass(const gph::Vec3 &lpos, const gph::Vec3 &ltarg, float lfov, float znear, float zfar)
+{
+	shadow_pass = true;
+
+	glPushAttrib(GL_ENABLE_BIT | GL_COLOR_BUFFER_BIT);
+	glDisable(GL_LIGHTING);
+	glColorMask(0, 0, 0, 0);
+	glDepthMask(1);
+
+	Matrix4x4 viewmat;
+	glGetFloatv(GL_MODELVIEW_MATRIX, viewmat[0]);
+	viewmat.transpose();
+
+	Matrix4x4 lt_viewmat, lt_projmat;
+	lt_projmat.set_perspective(DEG_TO_RAD(lfov) * 2.0, 1.0, znear, zfar);
+	lt_viewmat.set_lookat(Vector3(lpos.x, lpos.y, lpos.z), Vector3(ltarg.x, ltarg.y, ltarg.z), Vector3(0, 1, 0));
+	Matrix4x4 smat = lt_projmat * lt_viewmat * viewmat.inverse();
+	smat.transpose();
+
+	memcpy(shadow_mat[0], smat[0], 16 * sizeof(float));
+
+	glMatrixMode(GL_PROJECTION);
+	glPushMatrix();
+	glLoadTransposeMatrixf(lt_projmat[0]);
+
+	glMatrixMode(GL_MODELVIEW);
+	glPushMatrix();
+	glLoadTransposeMatrixf(lt_viewmat[0]);
+
+
+	/*gph::Mat4 viewmat;
+	glGetFloatv(GL_MODELVIEW_MATRIX, viewmat[0]);
+
+	gph::Mat4 lt_viewmat, lt_projmat;
+	lt_projmat.perspective(deg_to_rad(lfov) * 2.0, 1.0, znear, zfar);
+	lt_viewmat.inv_lookat(lpos, ltarg, gph::Vec3(0, 1, 0));
+	shadow_mat = lt_projmat * lt_viewmat * viewmat.inverse();
+	//shadow_mat = viewmat.inverse() * lt_viewmat * lt_projmat;
+	shadow_mat.print();
+
+	glMatrixMode(GL_PROJECTION);
+	glPushMatrix();
+	glLoadMatrixf(lt_projmat[0]);
+
+	glMatrixMode(GL_MODELVIEW);
+	glPushMatrix();
+	glLoadMatrixf(lt_viewmat[0]);
+	*/
+
+	glGetIntegerv(GL_VIEWPORT, prev_vp);
+	glViewport(0, 0, tex_sz, tex_sz);
+
+	glBindFramebuffer(GL_FRAMEBUFFER, fbo);
+
+	glPolygonOffset(2, 2);
+	glEnable(GL_POLYGON_OFFSET_FILL);
+
+	glClear(GL_DEPTH_BUFFER_BIT);
+	glUseProgram(0);
+}
+
+
+void end_shadow_pass()
+{
+	shadow_pass = false;
+
+	glBindFramebuffer(GL_FRAMEBUFFER, 0);
+
+	glViewport(prev_vp[0], prev_vp[1], prev_vp[2], prev_vp[3]);
+
+	glMatrixMode(GL_PROJECTION);
+	glPopMatrix();
+	glMatrixMode(GL_MODELVIEW);
+	glPopMatrix();
+
+	glPopAttrib();
+}
+
+gph::Mat4 get_shadow_matrix()
+{
+	return shadow_mat;
+}
+
+unsigned int get_shadow_tex()
+{
+	return depth_tex;
+}