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-rw-r--r--progs/demos/shadowtex.c328
1 files changed, 282 insertions, 46 deletions
diff --git a/progs/demos/shadowtex.c b/progs/demos/shadowtex.c
index b32fb45b4fa..59253e8c1e3 100644
--- a/progs/demos/shadowtex.c
+++ b/progs/demos/shadowtex.c
@@ -9,6 +9,7 @@
* Added GL_EXT_packed_depth_stencil support on 15 March 2006.
* Added GL_EXT_framebuffer_object support on 27 March 2006.
* Removed old SGIX extension support on 5 April 2006.
+ * Added vertex / fragment program support on 7 June 2007 (Ian Romanick).
*
* Copyright (C) 1999-2006 Brian Paul All Rights Reserved.
*
@@ -34,6 +35,7 @@
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
+#include <string.h>
#include <math.h>
#include <GL/glut.h>
#include "showbuffer.h"
@@ -67,8 +69,27 @@ static GLboolean NeedNewShadowMap = GL_FALSE;
static GLuint ShadowTexture, GrayTexture;
static GLuint ShadowFBO;
+static GLfloat lightModelview[16];
+static GLfloat lightProjection[16];
+
+static GLuint vert_prog;
+static GLuint frag_progs[3];
+static GLuint curr_frag = 0;
+static GLuint max_frag = 1;
+
+#define NUM_FRAG_MODES 3
+static const char *FragProgNames[] = {
+ "fixed-function",
+ "program without \"OPTION ARB_fragment_program_shadow\"",
+ "program with \"OPTION ARB_fragment_program_shadow\"",
+};
+
static GLboolean HaveFBO = GL_FALSE;
static GLboolean UseFBO = GL_FALSE;
+static GLboolean HaveVP = GL_FALSE;
+static GLboolean HaveFP = GL_FALSE;
+static GLboolean HaveFP_Shadow = GL_FALSE;
+static GLboolean UseVP = GL_FALSE;
static GLboolean HavePackedDepthStencil = GL_FALSE;
static GLboolean UsePackedDepthStencil = GL_FALSE;
static GLboolean HaveEXTshadowFuncs = GL_FALSE;
@@ -91,6 +112,103 @@ static GLuint DisplayMode;
+#define MAT4_MUL(dest_vec, src_mat, src_vec) \
+ "DP4 " dest_vec ".x, " src_mat "[0], " src_vec ";\n" \
+ "DP4 " dest_vec ".y, " src_mat "[1], " src_vec ";\n" \
+ "DP4 " dest_vec ".z, " src_mat "[2], " src_vec ";\n" \
+ "DP4 " dest_vec ".w, " src_mat "[3], " src_vec ";\n"
+
+#define MAT3_MUL(dest_vec, src_mat, src_vec) \
+ "DP3 " dest_vec ".x, " src_mat "[0], " src_vec ";\n" \
+ "DP3 " dest_vec ".y, " src_mat "[1], " src_vec ";\n" \
+ "DP3 " dest_vec ".z, " src_mat "[2], " src_vec ";\n"
+
+#define NORMALIZE(dest, src) \
+ "DP3 " dest ".w, " src ", " src ";\n" \
+ "RSQ " dest ".w, " dest ".w;\n" \
+ "MUL " dest ", " src ", " dest ".w;\n"
+
+/**
+ * Vertex program for shadow mapping.
+ */
+static const char vert_code[] =
+ "!!ARBvp1.0\n"
+ "ATTRIB iPos = vertex.position;\n"
+ "ATTRIB iNorm = vertex.normal;\n"
+
+ "PARAM mvinv[4] = { state.matrix.modelview.invtrans };\n"
+ "PARAM mvp[4] = { state.matrix.mvp };\n"
+ "PARAM mv[4] = { state.matrix.modelview };\n"
+ "PARAM texmat[4] = { state.matrix.texture[0] };\n"
+ "PARAM lightPos = state.light[0].position;\n"
+ "PARAM ambientCol = state.lightprod[0].ambient;\n"
+ "PARAM diffuseCol = state.lightprod[0].diffuse;\n"
+
+ "TEMP n, lightVec;\n"
+ "ALIAS V = lightVec;\n"
+ "ALIAS NdotL = n;\n"
+
+ "OUTPUT oPos = result.position;\n"
+ "OUTPUT oColor = result.color;\n"
+ "OUTPUT oTex = result.texcoord[0];\n"
+
+ /* Transform the vertex to clip coordinates. */
+ MAT4_MUL("oPos", "mvp", "iPos")
+
+ /* Transform the vertex to eye coordinates. */
+ MAT4_MUL("V", "mv", "iPos")
+
+ /* Transform the vertex to projected light coordinates. */
+ MAT4_MUL("oTex", "texmat", "iPos")
+
+ /* Transform the normal to eye coordinates. */
+ MAT3_MUL("n", "mvinv", "iNorm")
+
+ /* Calculate the vector from the vertex to the light in eye
+ * coordinates.
+ */
+ "SUB lightVec, lightPos, V;\n"
+ NORMALIZE("lightVec", "lightVec")
+
+ /* Compute diffuse lighting coefficient.
+ */
+ "DP3 NdotL.x, n, lightVec;\n"
+ "MAX NdotL.x, NdotL.x, {0.0};\n"
+ "MIN NdotL.x, NdotL.x, {1.0};\n"
+
+ /* Accumulate color contributions.
+ */
+ "MOV oColor, diffuseCol;\n"
+ "MAD oColor.xyz, NdotL.x, diffuseCol, ambientCol;\n"
+ "END\n"
+ ;
+
+static const char frag_code[] =
+ "!!ARBfp1.0\n"
+
+ "TEMP shadow, temp;\n"
+
+ "TXP shadow, fragment.texcoord[0], texture[0], 2D;\n"
+ "RCP temp.x, fragment.texcoord[0].w;\n"
+ "MUL temp.x, temp.x, fragment.texcoord[0].z;\n"
+ "SGE shadow, shadow.x, temp.x;\n"
+ "MUL result.color.rgb, fragment.color, shadow.x;\n"
+ "MOV result.color.a, fragment.color;\n"
+ "END\n"
+ ;
+
+static const char frag_shadow_code[] =
+ "!!ARBfp1.0\n"
+ "OPTION ARB_fragment_program_shadow;\n"
+
+ "TEMP shadow;\n"
+
+ "TXP shadow, fragment.texcoord[0], texture[0], SHADOW2D;\n"
+ "MUL result.color.rgb, fragment.color, shadow.x;\n"
+ "MOV result.color.a, fragment.color.a;\n"
+ "END\n"
+ ;
+
static void
DrawScene(void)
{
@@ -134,27 +252,56 @@ DrawScene(void)
}
-/*
- * Load the GL_TEXTURE matrix with the projection from the light
- * source's point of view.
+/**
+ * Calculate modelview and project matrices for the light
+ *
+ * Stores the results in \c lightProjection (projection matrix) and
+ * \c lightModelview (modelview matrix).
*/
static void
MakeShadowMatrix(const GLfloat lightPos[4], const GLfloat spotDir[3],
GLfloat spotAngle, GLfloat shadowNear, GLfloat shadowFar)
{
- GLfloat d;
-
- glMatrixMode(GL_TEXTURE);
+ /* compute frustum to enclose spot light cone */
+ const GLfloat d = shadowNear * tan(spotAngle);
+
+ glMatrixMode(GL_PROJECTION);
+ glPushMatrix();
glLoadIdentity();
- glTranslatef(0.5, 0.5, 0.5 + Bias);
- glScalef(0.5, 0.5, 0.5);
- d = shadowNear * tan(spotAngle);
glFrustum(-d, d, -d, d, shadowNear, shadowFar);
+ glGetFloatv(GL_PROJECTION_MATRIX, lightProjection);
+ glPopMatrix();
+
+ glMatrixMode(GL_MODELVIEW);
+ glPushMatrix();
+ glLoadIdentity();
gluLookAt(lightPos[0], lightPos[1], lightPos[2],
lightPos[0] + spotDir[0],
lightPos[1] + spotDir[1],
lightPos[2] + spotDir[2],
- 0, 1, 0);
+ 0.0, 1.0, 0.0);
+ glGetFloatv(GL_MODELVIEW_MATRIX, lightModelview);
+ glPopMatrix();
+}
+
+
+/**
+ * Load \c GL_TEXTURE matrix with light's MVP matrix.
+ */
+static void SetShadowTextureMatrix(void)
+{
+ static const GLfloat biasMatrix[16] = {
+ 0.5, 0.0, 0.0, 0.0,
+ 0.0, 0.5, 0.0, 0.0,
+ 0.0, 0.0, 0.5, 0.0,
+ 0.5, 0.5, 0.5, 1.0,
+ };
+
+ glMatrixMode(GL_TEXTURE);
+ glLoadMatrixf(biasMatrix);
+ glTranslatef(0.0, 0.0, Bias);
+ glMultMatrixf(lightProjection);
+ glMultMatrixf(lightModelview);
glMatrixMode(GL_MODELVIEW);
}
@@ -258,7 +405,6 @@ RenderShadowMap(void)
{
GLenum depthFormat; /* GL_DEPTH_COMPONENT or GL_DEPTH_STENCIL_EXT */
GLenum depthType; /* GL_UNSIGNED_INT_24_8_EXT or GL_UNSIGNED_INT */
- float d;
if (WindowWidth >= 1024 && WindowHeight >= 1024) {
ShadowTexWidth = ShadowTexHeight = 1024;
@@ -283,27 +429,34 @@ RenderShadowMap(void)
depthType = GL_UNSIGNED_INT;
}
- /* compute frustum to enclose spot light cone */
- d = ShadowNear * tan(SpotAngle);
-
glMatrixMode(GL_PROJECTION);
- glLoadIdentity();
- glFrustum(-d, d, -d, d, ShadowNear, ShadowFar);
+ glLoadMatrixf(lightProjection);
+
glMatrixMode(GL_MODELVIEW);
- glLoadIdentity();
- gluLookAt(LightPos[0], LightPos[1], LightPos[2], /* from */
- 0, 0, 0, /* target */
- 0, 1, 0); /* up */
+ glLoadMatrixf(lightModelview);
if (UseFBO) {
+ GLenum fbo_status;
+
glTexImage2D(GL_TEXTURE_2D, 0, depthFormat,
ShadowTexWidth, ShadowTexHeight, 0,
depthFormat, depthType, NULL);
+
+ /* Set the filter mode so that the texture is texture-complete.
+ * Otherwise it will cause the framebuffer to fail the framebuffer
+ * completeness test.
+ */
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+
glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, ShadowFBO);
glDrawBuffer(GL_NONE);
glReadBuffer(GL_NONE);
- assert(glCheckFramebufferStatusEXT(GL_FRAMEBUFFER_EXT)
- == GL_FRAMEBUFFER_COMPLETE_EXT);
+
+ fbo_status = glCheckFramebufferStatusEXT(GL_FRAMEBUFFER_EXT);
+ if (fbo_status != GL_FRAMEBUFFER_COMPLETE_EXT) {
+ fprintf(stderr, "FBO not complete! status = 0x%04x\n", fbo_status);
+ assert(fbo_status == GL_FRAMEBUFFER_COMPLETE_EXT);
+ }
}
assert(!glIsEnabled(GL_TEXTURE_1D));
@@ -376,10 +529,8 @@ ShowShadowMap(void)
DisableTexgen();
/* interpret texture's depth values as luminance values */
-#if defined(GL_ARB_shadow)
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_MODE_ARB, GL_NONE);
glTexParameteri(GL_TEXTURE_2D, GL_DEPTH_TEXTURE_MODE_ARB, GL_LUMINANCE);
-#endif
glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
glBegin(GL_POLYGON);
@@ -407,6 +558,7 @@ Display(void)
LightPos, SpotDir);
if (NeedNewShadowMap) {
+ MakeShadowMatrix(LightPos, SpotDir, SpotAngle, ShadowNear, ShadowFar);
RenderShadowMap();
NeedNewShadowMap = GL_FALSE;
}
@@ -444,12 +596,11 @@ Display(void)
}
if (DisplayMode == SHOW_DEPTH_MAPPING) {
-#if defined(GL_ARB_shadow)
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_MODE_ARB, GL_NONE);
-#endif
glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
glEnable(GL_TEXTURE_2D);
- MakeShadowMatrix(LightPos, SpotDir, SpotAngle, ShadowNear, ShadowFar);
+
+ SetShadowTextureMatrix();
EnableIdentityTexgen();
}
else if (DisplayMode == SHOW_DISTANCE) {
@@ -463,20 +614,42 @@ Display(void)
}
else {
assert(DisplayMode == SHOW_SHADOWS);
-#if defined(GL_ARB_shadow)
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_MODE_ARB,
GL_COMPARE_R_TO_TEXTURE_ARB);
-#endif
- glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
+
+ if (curr_frag > 0) {
+ glEnable(GL_FRAGMENT_PROGRAM_ARB);
+ }
+ else {
+ glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
+ }
glEnable(GL_TEXTURE_2D);
- MakeShadowMatrix(LightPos, SpotDir, SpotAngle, ShadowNear, ShadowFar);
- EnableIdentityTexgen();
+
+ SetShadowTextureMatrix();
+
+ if (UseVP) {
+ glEnable(GL_VERTEX_PROGRAM_ARB);
+ }
+ else {
+ glEnable(GL_LIGHTING);
+ EnableIdentityTexgen();
+ }
}
DrawScene();
- DisableTexgen();
- glDisable(GL_TEXTURE_1D);
+ if (UseVP) {
+ glDisable(GL_VERTEX_PROGRAM_ARB);
+ }
+ else {
+ DisableTexgen();
+ glDisable(GL_LIGHTING);
+ }
+
+ if (curr_frag > 0) {
+ glDisable(GL_FRAGMENT_PROGRAM_ARB);
+ }
+
glDisable(GL_TEXTURE_2D);
}
@@ -548,6 +721,14 @@ Key(unsigned char key, int x, int y)
case 'm':
DisplayMode = SHOW_DEPTH_MAPPING;
break;
+ case 'M':
+ curr_frag = (1 + curr_frag) % max_frag;
+ printf("Using fragment %s\n", FragProgNames[curr_frag]);
+
+ if (HaveFP) {
+ glBindProgramARB(GL_FRAGMENT_PROGRAM_ARB, frag_progs[curr_frag]);
+ }
+ break;
case 'n':
case 's':
case ' ':
@@ -559,10 +740,8 @@ Key(unsigned char key, int x, int y)
if (Operator >= 8)
Operator = 0;
printf("Operator: %s\n", OperatorName[Operator]);
-#if defined(GL_ARB_shadow)
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_FUNC_ARB,
OperatorFunc[Operator]);
-#endif
}
break;
case 'p':
@@ -579,6 +758,11 @@ Key(unsigned char key, int x, int y)
NeedNewShadowMap = GL_TRUE;
}
break;
+ case 'v':
+ UseVP = !UseVP && HaveVP;
+ printf("Using vertex %s mode.\n",
+ UseVP ? "program" : "fixed-function");
+ break;
case 'z':
Zrot -= step;
break;
@@ -633,28 +817,62 @@ SpecialKey(int key, int x, int y)
}
+/* A helper for finding errors in program strings */
+static int FindLine( const char *program, int position )
+{
+ int i, line = 1;
+ for (i = 0; i < position; i++) {
+ if (program[i] == '\n')
+ line++;
+ }
+ return line;
+}
+
+
+static GLuint
+compile_program(GLenum target, const char *code)
+{
+ GLuint p;
+ GLint errorPos;
+
+
+ glGenProgramsARB(1, & p);
+
+ glBindProgramARB(target, p);
+ glProgramStringARB(target, GL_PROGRAM_FORMAT_ASCII_ARB,
+ strlen(code), code);
+ glGetIntegerv(GL_PROGRAM_ERROR_POSITION_ARB, &errorPos);
+ if (glGetError() != GL_NO_ERROR || errorPos != -1) {
+ int l = FindLine(code, errorPos);
+ printf("Fragment Program Error (pos=%d line=%d): %s\n", errorPos, l,
+ (char *) glGetString(GL_PROGRAM_ERROR_STRING_ARB));
+ exit(0);
+ }
+
+ glBindProgramARB(target, 0);
+ return p;
+}
+
static void
Init(void)
{
static const GLfloat borderColor[4] = {1.0, 0.0, 0.0, 0.0};
-#if defined(GL_ARB_depth_texture) && defined(GL_ARB_shadow)
if (!glutExtensionSupported("GL_ARB_depth_texture") ||
!glutExtensionSupported("GL_ARB_shadow")) {
-#else
- if (1) {
-#endif
printf("Sorry, this demo requires the GL_ARB_depth_texture and GL_ARB_shadow extensions\n");
exit(1);
}
printf("Using GL_ARB_depth_texture and GL_ARB_shadow\n");
-#if defined(GL_ARB_shadow_ambient)
+ HaveVP = glutExtensionSupported("GL_ARB_vertex_program");
+ HaveFP = glutExtensionSupported("GL_ARB_fragment_program");
+ HaveFP_Shadow = glutExtensionSupported("GL_ARB_fragment_program_shadow");
+
HaveShadowAmbient = glutExtensionSupported("GL_ARB_shadow_ambient");
if (HaveShadowAmbient) {
printf("and GL_ARB_shadow_ambient\n");
}
-#endif
HaveEXTshadowFuncs = glutExtensionSupported("GL_EXT_shadow_funcs");
@@ -677,15 +895,12 @@ Init(void)
glTexParameterfv(GL_TEXTURE_2D, GL_TEXTURE_BORDER_COLOR, borderColor);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
-#if defined(GL_ARB_shadow)
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_MODE_ARB,
GL_COMPARE_R_TO_TEXTURE_ARB);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_FUNC_ARB, GL_LEQUAL);
-#endif
+
if (HaveShadowAmbient) {
-#if defined(GL_ARB_shadow_ambient)
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_FAIL_VALUE_ARB, 0.3);
-#endif
}
#if defined(GL_EXT_framebuffer_object)
@@ -720,6 +935,25 @@ Init(void)
256, 0, GL_LUMINANCE, GL_UNSIGNED_BYTE, image);
}
+ if (HaveVP) {
+ vert_prog = compile_program(GL_VERTEX_PROGRAM_ARB, vert_code);
+ glBindProgramARB(GL_VERTEX_PROGRAM_ARB, vert_prog);
+ }
+
+ max_frag = 1;
+ frag_progs[0] = 0;
+
+ if (HaveFP) {
+ frag_progs[1] = compile_program(GL_FRAGMENT_PROGRAM_ARB, frag_code);
+ max_frag = 2;
+ }
+
+ if (HaveFP && HaveFP_Shadow) {
+ frag_progs[2] = compile_program(GL_FRAGMENT_PROGRAM_ARB,
+ frag_shadow_code);
+ max_frag = 3;
+ }
+
glEnable(GL_DEPTH_TEST);
glEnable(GL_LIGHTING);
glEnable(GL_LIGHT0);
@@ -738,6 +972,8 @@ PrintHelp(void)
printf(" f = toggle nearest/bilinear texture filtering\n");
printf(" b/B = decrease/increase shadow map Z bias\n");
printf(" p = toggle use of packed depth/stencil\n");
+ printf(" M = cycle through fragment program modes\n");
+ printf(" v = toggle vertex program modes\n");
printf(" cursor keys = rotate scene\n");
printf(" <shift> + cursor keys = rotate light source\n");
if (HaveEXTshadowFuncs)
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-26 23:45:49 +0000