demos: remove OSMESA stuff from Makefile
[mesa.git] / progs / demos / shadowtex.c
index b11c6f5363012de096639f888ce010b8d7123f45..4787f0f29d2aa6b86e597ffe970e51cf2bfba71f 100644 (file)
@@ -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 +69,28 @@ 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 HaveShadow = GL_FALSE;
 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 +113,103 @@ 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 +253,56 @@ 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 +406,6 @@ 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;
@@ -283,17 +430,11 @@ 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;
@@ -389,10 +530,11 @@ 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);
+   if (HaveShadow) {
+      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);
@@ -420,6 +562,7 @@ Display(void)
                    LightPos, SpotDir);
 
    if (NeedNewShadowMap) {
+      MakeShadowMatrix(LightPos, SpotDir, SpotAngle, ShadowNear, ShadowFar);
       RenderShadowMap();
       NeedNewShadowMap = GL_FALSE;
    }
@@ -457,12 +600,13 @@ Display(void)
       }
 
       if (DisplayMode == SHOW_DEPTH_MAPPING) {
-#if defined(GL_ARB_shadow)
-         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_MODE_ARB, GL_NONE);
-#endif
+         if (HaveShadow) {
+            glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_MODE_ARB, GL_NONE);
+         }
          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) {
@@ -476,19 +620,44 @@ 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 (HaveShadow) {
+            glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_MODE_ARB,
+                            GL_COMPARE_R_TO_TEXTURE_ARB);
+         }
+
+         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();
+      if (UseVP) {
+         glDisable(GL_VERTEX_PROGRAM_ARB);
+      }
+      else {
+         DisableTexgen();
+         glDisable(GL_LIGHTING);
+      }
+
+      if (curr_frag > 0) {
+         glDisable(GL_FRAGMENT_PROGRAM_ARB);
+      }
+
       glDisable(GL_TEXTURE_1D);
       glDisable(GL_TEXTURE_2D);
    }
@@ -561,6 +730,18 @@ Key(unsigned char key, int x, int y)
       case 'm':
          DisplayMode = SHOW_DEPTH_MAPPING;
          break;
+      case 'M':
+         curr_frag = (1 + curr_frag) % max_frag;
+         if (!HaveShadow && (curr_frag == 0)) {
+            curr_frag = 1;
+         }
+
+         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 ' ':
@@ -572,10 +753,10 @@ 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
+            if (HaveShadow) {
+               glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_FUNC_ARB,
+                               OperatorFunc[Operator]);
+            }
          }
          break;
       case 'p':
@@ -592,6 +773,11 @@ 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;
@@ -646,28 +832,76 @@ 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");
+   if (!glutExtensionSupported("GL_ARB_depth_texture")) {
+      printf("Sorry, this demo requires the GL_ARB_depth_texture extension\n");
+      exit(1);
+   }
+
+   HaveShadow = glutExtensionSupported("GL_ARB_shadow");
+   HaveVP = glutExtensionSupported("GL_ARB_vertex_program");
+   HaveFP = glutExtensionSupported("GL_ARB_fragment_program");
+   HaveFP_Shadow = glutExtensionSupported("GL_ARB_fragment_program_shadow");
+
+   if (!HaveShadow && !HaveFP) {
+      printf("Sorry, this demo requires either the GL_ARB_shadow extension "
+            "or the GL_ARB_fragment_program extension\n");
       exit(1);
    }
-   printf("Using GL_ARB_depth_texture and GL_ARB_shadow\n");
 
-#if defined(GL_ARB_shadow_ambient)
+   printf("Using GL_ARB_depth_texture\n");
+   if (HaveShadow) {
+      printf("and GL_ARB_shadow\n");
+   }
+
+   if (HaveFP) {
+      printf("and GL_ARB_fragment_program\n");
+   }
+
    HaveShadowAmbient = glutExtensionSupported("GL_ARB_shadow_ambient");
    if (HaveShadowAmbient) {
       printf("and GL_ARB_shadow_ambient\n");
    }
-#endif
 
    HaveEXTshadowFuncs = glutExtensionSupported("GL_EXT_shadow_funcs");
 
@@ -690,15 +924,15 @@ 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 (HaveShadow) {
+      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);
+   }
+
    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)
@@ -721,7 +955,6 @@ Init(void)
    glGenTextures(1, &GrayTexture);
    glBindTexture(GL_TEXTURE_1D, GrayTexture);
    glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_WRAP_S, GL_CLAMP);
-   glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_WRAP_T, GL_CLAMP);
    glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
    glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
    {
@@ -733,6 +966,30 @@ 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;
+   }
+
+   if (!HaveShadow) {
+      curr_frag = 1;
+      glBindProgramARB(GL_FRAGMENT_PROGRAM_ARB, frag_progs[curr_frag]);
+   }
+
    glEnable(GL_DEPTH_TEST);
    glEnable(GL_LIGHTING);
    glEnable(GL_LIGHT0);
@@ -751,6 +1008,8 @@ 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)