From ea5dc8a10beb55cd972c34d6b531158101b6773f Mon Sep 17 00:00:00 2001 From: Diederick Niehorster Date: Sun, 18 Nov 2012 15:41:03 +0000 Subject: [PATCH 1/1] can now also draw the normal vectors (seems very useful for instructive programs, something which FreeGLUT often gets used for). use the 'n' key in the shapes demo git-svn-id: svn+ssh://svn.code.sf.net/p/freeglut/code/trunk/freeglut/freeglut@1403 7f0cb862-5218-0410-a997-914c9d46530a --- include/GL/freeglut_ext.h | 2 + progs/demos/shapes/shapes.c | 9 +++- src/fg_geometry.c | 113 ++++++++++++++++++++++++++++++++++++------- src/fg_internal.h | 4 +- src/fg_state.c | 10 ++++ src/fg_structure.c | 1 + 6 files changed, 120 insertions(+), 19 deletions(-) diff --git a/include/GL/freeglut_ext.h b/include/GL/freeglut_ext.h index 98bb9d7..da6c7ee 100644 --- a/include/GL/freeglut_ext.h +++ b/include/GL/freeglut_ext.h @@ -86,6 +86,8 @@ #define GLUT_SKIP_STALE_MOTION_EVENTS 0x0204 +#define GLUT_OBJECTS_VISUALIZE_NORMALS 0x0205 + /* * New tokens for glutInitDisplayMode. * Only one GLUT_AUXn bit may be used at a time. diff --git a/progs/demos/shapes/shapes.c b/progs/demos/shapes/shapes.c index 6942c77..b2da232 100644 --- a/progs/demos/shapes/shapes.c +++ b/progs/demos/shapes/shapes.c @@ -420,6 +420,7 @@ static float ar; static GLboolean persProject = GL_TRUE; static GLboolean animateXRot = GL_FALSE; static GLboolean useShader = GL_FALSE; +static GLboolean visNormals = GL_FALSE; /* * These one-liners draw particular objects, fetching appropriate @@ -541,7 +542,7 @@ static const entry table [] = ENTRY (Sphere), ENTRY (Cone), ENTRY (Cylinder), - ENTRY (Cuboctahedron) + ENTRY (Cuboctahedron) /* This one doesn't work when in shader mode and is then skipped */ }; #undef ENTRY @@ -659,6 +660,7 @@ static void display(void) else { /* fixed function pipeline */ + glutSetOption(GLUT_OBJECTS_VISUALIZE_NORMALS,visNormals); /* Normals visualized or not? */ glMatrixMode(GL_PROJECTION); glLoadIdentity(); if (persProject) @@ -709,6 +711,8 @@ static void display(void) shapesPrintf (9, 1, "2D rotation (r)"); else shapesPrintf (9, 1, "1D rotation (r)"); + if (!useShader) + shapesPrintf (10, 1, "visualizing normals: %i (n)",visNormals); } else { /* print to command line instead */ printf ( "Shape %d slides %d stacks %d\n", function_index, slices, stacks ) ; @@ -757,6 +761,9 @@ key(unsigned char key, int x, int y) case 'S': case 's': useShader=!useShader; break; + case 'N': + case 'n': visNormals=!visNormals; break; + default: break; } diff --git a/src/fg_geometry.c b/src/fg_geometry.c index 3e50e79..066a0d3 100644 --- a/src/fg_geometry.c +++ b/src/fg_geometry.c @@ -34,20 +34,24 @@ have a nice code order below */ #ifndef GL_ES_VERSION_2_0 static void fghDrawGeometryWire11(GLfloat *vertices, GLfloat *normals, - GLushort *vertIdxs, GLsizei numParts, GLsizei numVertPerPart, GLenum vertexMode, - GLushort *vertIdxs2, GLsizei numParts2, GLsizei numVertPerPart2 + GLushort *vertIdxs, GLsizei numParts, GLsizei numVertPerPart, GLenum vertexMode, + GLushort *vertIdxs2, GLsizei numParts2, GLsizei numVertPerPart2 ); static void fghDrawGeometrySolid11(GLfloat *vertices, GLfloat *normals, GLsizei numVertices, - GLushort *vertIdxs, GLsizei numParts, GLsizei numVertIdxsPerPart); + GLushort *vertIdxs, GLsizei numParts, GLsizei numVertIdxsPerPart); #endif static void fghDrawGeometryWire20(GLfloat *vertices, GLfloat *normals, GLsizei numVertices, - GLushort *vertIdxs, GLsizei numParts, GLsizei numVertPerPart, GLenum vertexMode, - GLushort *vertIdxs2, GLsizei numParts2, GLsizei numVertPerPart2, - GLint attribute_v_coord, GLint attribute_v_normal + GLushort *vertIdxs, GLsizei numParts, GLsizei numVertPerPart, GLenum vertexMode, + GLushort *vertIdxs2, GLsizei numParts2, GLsizei numVertPerPart2, + GLint attribute_v_coord, GLint attribute_v_normal ); static void fghDrawGeometrySolid20(GLfloat *vertices, GLfloat *normals, GLsizei numVertices, - GLushort *vertIdxs, GLsizei numParts, GLsizei numVertIdxsPerPart, - GLint attribute_v_coord, GLint attribute_v_normal); + GLushort *vertIdxs, GLsizei numParts, GLsizei numVertIdxsPerPart, + GLint attribute_v_coord, GLint attribute_v_normal); +/* declare function for generating visualization of normals */ +static void fghGenerateNormalVisualization(GLfloat *vertices, GLfloat *normals, GLsizei numVertices, + GLushort *vertIdxs, GLsizei numParts, GLsizei numVertIdxsPerPart); +static void fghDrawNormalVisualization(); /* Drawing geometry: * Explanation of the functions has to be separate for the polyhedra and @@ -116,8 +120,8 @@ static void fghDrawGeometrySolid20(GLfloat *vertices, GLfloat *normals, GLsizei * Feel free to contribute better naming ;) */ static void fghDrawGeometryWire(GLfloat *vertices, GLfloat *normals, GLsizei numVertices, - GLushort *vertIdxs, GLsizei numParts, GLsizei numVertPerPart, GLenum vertexMode, - GLushort *vertIdxs2, GLsizei numParts2, GLsizei numVertPerPart2 + GLushort *vertIdxs, GLsizei numParts, GLsizei numVertPerPart, GLenum vertexMode, + GLushort *vertIdxs2, GLsizei numParts2, GLsizei numVertPerPart2 ) { GLint attribute_v_coord = fgStructure.CurrentWindow->Window.attribute_v_coord; @@ -176,8 +180,19 @@ static void fghDrawGeometrySolid(GLfloat *vertices, GLfloat *normals, GLsizei nu attribute_v_coord, attribute_v_normal); #ifndef GL_ES_VERSION_2_0 else + { fghDrawGeometrySolid11(vertices, normals, numVertices, vertIdxs, numParts, numVertIdxsPerPart); + + if (fgStructure.CurrentWindow->State.VisualizeNormals) + { + /* generate normals for each vertex to be drawn as well */ + fghGenerateNormalVisualization(vertices, normals, numVertices, + vertIdxs, numParts, numVertIdxsPerPart); + /* draw normals for each vertex as well */ + fghDrawNormalVisualization(); + } + } #endif } @@ -186,8 +201,8 @@ static void fghDrawGeometrySolid(GLfloat *vertices, GLfloat *normals, GLsizei nu /* Version for OpenGL (ES) 1.1 */ #ifndef GL_ES_VERSION_2_0 static void fghDrawGeometryWire11(GLfloat *vertices, GLfloat *normals, - GLushort *vertIdxs, GLsizei numParts, GLsizei numVertPerPart, GLenum vertexMode, - GLushort *vertIdxs2, GLsizei numParts2, GLsizei numVertPerPart2 + GLushort *vertIdxs, GLsizei numParts, GLsizei numVertPerPart, GLenum vertexMode, + GLushort *vertIdxs2, GLsizei numParts2, GLsizei numVertPerPart2 ) { int i; @@ -217,7 +232,7 @@ static void fghDrawGeometryWire11(GLfloat *vertices, GLfloat *normals, static void fghDrawGeometrySolid11(GLfloat *vertices, GLfloat *normals, GLsizei numVertices, - GLushort *vertIdxs, GLsizei numParts, GLsizei numVertIdxsPerPart) + GLushort *vertIdxs, GLsizei numParts, GLsizei numVertIdxsPerPart) { int i; @@ -243,10 +258,9 @@ static void fghDrawGeometrySolid11(GLfloat *vertices, GLfloat *normals, GLsizei /* Version for OpenGL (ES) >= 2.0 */ static void fghDrawGeometryWire20(GLfloat *vertices, GLfloat *normals, GLsizei numVertices, - GLushort *vertIdxs, GLsizei numParts, GLsizei numVertPerPart, GLenum vertexMode, - GLushort *vertIdxs2, GLsizei numParts2, GLsizei numVertPerPart2, - GLint attribute_v_coord, GLint attribute_v_normal - ) + GLushort *vertIdxs, GLsizei numParts, GLsizei numVertPerPart, GLenum vertexMode, + GLushort *vertIdxs2, GLsizei numParts2, GLsizei numVertPerPart2, + GLint attribute_v_coord, GLint attribute_v_normal) { GLuint vbo_coords = 0, vbo_normals = 0, ibo_elements = 0, ibo_elements2 = 0; @@ -447,6 +461,71 @@ static void fghDrawGeometrySolid20(GLfloat *vertices, GLfloat *normals, GLsizei /** + * Generate vertex indices for visualizing the normals. + */ +static GLfloat *verticesForNormalVisualization; +static GLushort numNormalVertices = 0; +static void fghGenerateNormalVisualization(GLfloat *vertices, GLfloat *normals, GLsizei numVertices, + GLushort *vertIdxs, GLsizei numParts, GLsizei numVertIdxsPerPart) +{ + GLushort i,j; + /* calc number of vertices to generate, allocate. TODO: FREE again after draw! + * two for each vertex in the input shape + */ + if (!vertIdxs) + numNormalVertices = numVertices * 2; + else + numNormalVertices = numParts * numVertIdxsPerPart * 2; + verticesForNormalVisualization = malloc(numNormalVertices*3 * sizeof(GLfloat)); + + /* Now generate vertices for lines to draw the normals */ + if (!vertIdxs) + { + for (i=0,j=0; iState.VisualizeNormals = value; + break; + default: fgWarning( "glutSetOption(): missing enum handle %d", eWhat ); break; @@ -205,6 +210,11 @@ int FGAPIENTRY glutGet( GLenum eWhat ) case GLUT_SKIP_STALE_MOTION_EVENTS: return fgState.SkipStaleMotion; + case GLUT_OBJECTS_VISUALIZE_NORMALS: + if( fgStructure.CurrentWindow == NULL ) + return GL_FALSE; + return fgStructure.CurrentWindow->State.VisualizeNormals; + default: return fgPlatformGlutGet ( eWhat ); break; diff --git a/src/fg_structure.c b/src/fg_structure.c index 7c2c143..8a5b4f5 100644 --- a/src/fg_structure.c +++ b/src/fg_structure.c @@ -98,6 +98,7 @@ SFG_Window* fgCreateWindow( SFG_Window* parent, const char* title, window->State.IgnoreKeyRepeat = GL_FALSE; window->State.KeyRepeating = GL_FALSE; window->State.IsFullscreen = GL_FALSE; + window->State.VisualizeNormals= GL_FALSE; /* * Open the window now. The fgOpenWindow() function is system -- 1.7.10.4