sync up

9 files changed, 103 insertions, 78 deletions

diff --git a/sdl/GL_notes.txt b/sdl/GL_notes.txt
index 0a19bbb..23795e9 100644
--- a/sdl/GL_notes.txt
+++ b/sdl/GL_notes.txt
@@ -75,3 +75,9 @@ Vertex Shader--you can write code for tasks such as:
 - Lighting per vertex or computing values for lighting per pixel
 - Color computation
 
+Fixed Functionality Pipeline
+- glTranslatef: can be mimicked by building m3dTranslationMatrix44f
+- glRotatef: can be mimicked by building m3dRotationMatrix44f
+- Both of the matrices can be combined by multiplying them, and loaded by using glLoadMatrixf,
+  but more efficient way is to let OpenGL do the multiplication for you by using glMultMatrixf
+
diff --git a/sdl/Makefile b/sdl/Makefile
index 1ff2958..a2309bb 100644
--- a/sdl/Makefile
+++ b/sdl/Makefile
@@ -1,9 +1,3 @@
-#
-#
-# Note: object targets are not valid and get recompiled everytime simply
-#       because they do not point to a valid location
-#
-
 BIN = pyramid
 SRC = pyramid.c math3d.c gltools.c glframe.c shader.c platform.c window.c
 CC = gcc
@@ -21,32 +15,31 @@ SDL_image_CFLAGS := $(shell pkg-config --cflags SDL_image)
 SDL_image_LDFLAGS := $(shell pkg-config --libs SDL_image)
 
 OBJ_DIR = obj
-OBJ_REL = $(addsuffix .o, $(subst .c,,$(SRC)))
-OBJ_ABS = $(addprefix $(OBJ_DIR)/, $(addsuffix .o, $(subst .c,,$(SRC))))
+OBJ_FILES = $(addprefix $(OBJ_DIR)/, $(addsuffix .o, $(subst .c,,$(SRC))))
 
-$(BIN): $(OBJ_DIR) $(OBJ_REL)
-	$(CC) $(LDFLAGS) $(SDL_LDFLAGS) $(SDL_image_LDFLAGS) $(OBJ_ABS) -o $@
+$(BIN): $(OBJ_DIR) $(OBJ_FILES)
+	$(CC) $(LDFLAGS) $(SDL_LDFLAGS) $(SDL_image_LDFLAGS) $(OBJ_FILES) -o $@
 
-pyramid.o: %.o: %.c math3d.h gltools.h glframe.h platform.h
-	$(CC) -c $(CFLAGS) $(SDL_CFLAGS) $(SDL_image_CFLAGS) $< -o $(OBJ_DIR)/$@
+$(OBJ_DIR)/pyramid.o: $(OBJ_DIR)/%.o: %.c math3d.h gltools.h glframe.h platform.h
+	$(CC) -c $(CFLAGS) $(SDL_CFLAGS) $(SDL_image_CFLAGS) $< -o $@
 
-math3d.o: %.o: %.c %.h
-	$(CC) -c $(CFLAGS) $< -o $(OBJ_DIR)/$@
+$(OBJ_DIR)/math3d.o: $(OBJ_DIR)/%.o: %.c %.h
+	$(CC) -c $(CFLAGS) $< -o $@
 
-gltools.o: %.o: %.c %.h math3d.h
-	$(CC) -c $(CFLAGS) $< -o $(OBJ_DIR)/$@
+$(OBJ_DIR)/gltools.o: $(OBJ_DIR)/%.o: %.c %.h math3d.h
+	$(CC) -c $(CFLAGS) $< -o $@
 
-glframe.o: %.o: %.c %.h math3d.h
-	$(CC) -c $(CFLAGS) $< -o $(OBJ_DIR)/$@
+$(OBJ_DIR)/glframe.o: $(OBJ_DIR)/%.o: %.c %.h math3d.h
+	$(CC) -c $(CFLAGS) $< -o $@
 
-shader.o: %.o: %.c %.h
-	$(CC) -c $(CFLAGS) $< -o $(OBJ_DIR)/$@
+$(OBJ_DIR)/shader.o: $(OBJ_DIR)/%.o: %.c %.h
+	$(CC) -c $(CFLAGS) $< -o $@
 
-platform.o: %.o: %.c %.h
-	$(CC) -c $(CFLAGS) $(SDL_CFLAGS) $(SDL_image_CFLAGS) $< -o $(OBJ_DIR)/$@
+$(OBJ_DIR)/platform.o: $(OBJ_DIR)/%.o: %.c %.h
+	$(CC) -c $(CFLAGS) $(SDL_CFLAGS) $(SDL_image_CFLAGS) $< -o $@
 
-window.o: %.o: %.c %.h
-	$(CC) -c $(CFLAGS) $(SDL_CFLAGS) $(SDL_image_CFLAGS) $< -o $(OBJ_DIR)/$@
+$(OBJ_DIR)/window.o: $(OBJ_DIR)/%.o: %.c %.h
+	$(CC) -c $(CFLAGS) $(SDL_CFLAGS) $(SDL_image_CFLAGS) $< -o $@
 
 $(OBJ_DIR):
 	mkdir -p $(OBJ_DIR)
@@ -58,4 +51,4 @@ clean:
 	@rm -f $(BIN)
 
 info:
-	@echo $(OBJ_REL)
+	@echo $(OBJ_FILES)
diff --git a/sdl/glframe.c b/sdl/glframe.c
index fbf8cd6..16a91cb 100644
--- a/sdl/glframe.c
+++ b/sdl/glframe.c
@@ -2,8 +2,6 @@
  *
  * Camera
  *
- * notes: we could make these functions to be inlined, but they would need
- * to be moved into a header
  *
  */
 
@@ -63,6 +61,18 @@ inline void glframe_get_camera_orientation(GLFrame *frame, M3DMatrix44f m)
 /* perform viewing or modeling transformations */
 inline void glframe_apply_camera_transform(GLFrame *frame, const int rot_only)
 {
+    if (rot_only)
+    {
+        gluLookAt(frame->v_location[0], frame->v_location[1], frame->v_location[2],
+                  frame->v_location[0] + frame->v_forward[0],
+                  frame->v_location[1] + frame->v_forward[1],
+                  frame->v_location[2] + frame->v_forward[2],
+                  frame->v_up[0], frame->v_up[1], frame->v_up[2]);
+
+        return;
+    }
+
+    /* do it the hard way */
     M3DMatrix44f m;
     glframe_get_camera_orientation(frame, m);
     glMultMatrixf(m);
@@ -70,14 +80,6 @@ inline void glframe_apply_camera_transform(GLFrame *frame, const int rot_only)
     if (!rot_only)
         glTranslatef(-frame->v_location[0], -frame->v_location[1],
                      -frame->v_location[2]);
-        
-#if 0
-    gluLookAt(frame->v_location[0], frame->v_location[1], frame->v_location[2],
-              frame->v_location[0] + frame->v_forward[0],
-              frame->v_location[1] + frame->v_forward[1],
-              frame->v_location[2] + frame->v_forward[2],
-              frame->v_up[0], frame->v_up[1], frame->v_up[2]);
-#endif                
 }
 
 inline void glframe_move_forward(GLFrame *frame, const float delta)
diff --git a/sdl/gltools.c b/sdl/gltools.c
index 7db2410..2c2c0c4 100644
--- a/sdl/gltools.c
+++ b/sdl/gltools.c
@@ -2,7 +2,7 @@
  *
  * OpenGL Tools
  *
- * notes: some function modify current color, just fyi
+ * notes: some function modify current color, just FYI
  *
  */
 
@@ -37,7 +37,7 @@ GLint gltWriteTGA(const char *szFileName)
         return 0;
     }
 
-    /* read bits from color buffer */
+    /* change how bits are stored */
     glPixelStorei(GL_PACK_ALIGNMENT, 1);
     glPixelStorei(GL_PACK_ROW_LENGTH, 0);
     glPixelStorei(GL_PACK_SKIP_ROWS, 0);
@@ -427,7 +427,6 @@ void gltDrawUnitAxes(void)
 }
 
 /* draw a torus (doughnut), using the current 1d texture for light shading */
-/* this funct accepts 4x4 trans matrix to be applied to the vertices */
 void gltDrawTorus(GLfloat majorRadius, GLfloat minorRadius, GLint numMajor, 
                   GLint numMinor)
 {
diff --git a/sdl/grass.tga b/sdl/grass.tga
new file mode 100644
index 0000000..81699a2
--- /dev/null
+++ b/sdl/grass.tga
diff --git a/sdl/math3d.c b/sdl/math3d.c
index ca60233..b22c530 100644
--- a/sdl/math3d.c
+++ b/sdl/math3d.c
@@ -4,9 +4,7 @@
  * 
  */
 
-#include <math.h>
 #include <stdio.h>
-#include <string.h>
 #include "math3d.h"
 
 void m3dFindNormalf(M3DVector3f result, const M3DVector3f point1, 
diff --git a/sdl/math3d.h b/sdl/math3d.h
index 875757c..d9d9117 100644
--- a/sdl/math3d.h
+++ b/sdl/math3d.h
@@ -111,8 +111,6 @@ static inline void m3dSetMatrixColumn44f(M3DMatrix44f dst, const M3DVector4f src
 	memcpy(dst + (4 * col), src, sizeof(float) * 4);
 }
 
-
-
 static inline void m3dLoadVector2f(M3DVector2f v, const float x, const float y)
 {
     v[0] = x;
diff --git a/sdl/platform.c b/sdl/platform.c
index 55f6555..7542d11 100644
--- a/sdl/platform.c
+++ b/sdl/platform.c
@@ -13,6 +13,7 @@
 /* few light arrays */
 GLfloat fNoLight[]     = { 0.0f, 0.0f, 0.0f, 0.0f    };
 GLfloat fLowLight[]    = { 0.25f, 0.25f, 0.25f, 1.0f };
+GLfloat fMedLight[]    = { 0.50f, 0.50f, 0.50f, 1.0f };
 GLfloat fBrightLight[] = { 1.0f, 1.0f, 1.0f, 1.0f    };
 
 /* light values and coordinates */
@@ -36,26 +37,29 @@ void setup_opengl(void)
     glFogf(GL_FOG_END, 20.0f);
     glFogi(GL_FOG_MODE, GL_LINEAR);   /* fog equation */
 
-    glEnable(GL_DEPTH_TEST);          /* hidden surface removal */
-    glFrontFace(GL_CCW);              /* counter clock-wise polygons face out */
-    glEnable(GL_CULL_FACE);           /* do not calculate inside of a pyramid */
+    glEnable(GL_DEPTH_TEST); /* hidden surface removal */
+    glFrontFace(GL_CCW);     /* counter clock-wise polygons face out */
+    glEnable(GL_CULL_FACE);  /* do not calculate inside of a pyramid */
+
+    /* enable lighting */
+    glEnable(GL_LIGHTING);
+
+    /* global illumination, ambient RGBA intensity of the entire scene */
+    glLightModelfv(GL_LIGHT_MODEL_AMBIENT, fLowLight);
 
     /* setup and enable light 0 */
-    /* ambient RGBA intensity of the entire scene */
-    glLightModelfv(GL_LIGHT_MODEL_AMBIENT, whiteLight);
-    glLightfv(GL_LIGHT0, GL_AMBIENT, sourceLight);
-    glLightfv(GL_LIGHT0, GL_DIFFUSE, fBrightLight);
+    glLightfv(GL_LIGHT0, GL_AMBIENT, fMedLight);
+    glLightfv(GL_LIGHT0, GL_DIFFUSE, fMedLight);
     glLightfv(GL_LIGHT0, GL_SPECULAR, fBrightLight);
     glLightfv(GL_LIGHT0, GL_POSITION, lightPos);
-
-    /* enable lighting */    
-    glEnable(GL_LIGHTING);
     glEnable(GL_LIGHT0);
 
     /* enable color tracking */
     glEnable(GL_COLOR_MATERIAL);
 
-    /* set Material properties to follow glColor values */
+    /* set material properties to follow glColor values */
+    /* all primitives specified after the glMaterial call are affected by the
+     * last values set, until another call to glMaterial is made */
     glColorMaterial(GL_FRONT, GL_AMBIENT_AND_DIFFUSE);
     glMaterialfv(GL_FRONT, GL_SPECULAR, fBrightLight);
     glMateriali(GL_FRONT, GL_SHININESS, 128);
@@ -67,34 +71,27 @@ void setup_opengl(void)
     glHint(GL_POINT_SMOOTH_HINT, GL_NICEST);
     glEnable(GL_LINE_SMOOTH);
     glHint(GL_LINE_SMOOTH_HINT, GL_NICEST);
-    /* screws up snowman */
+
+    /* screws up snowman, this has been replaced by superior multisampling */
     //glEnable(GL_POLYGON_SMOOTH);
     //glHint(GL_POLYGON_SMOOTH_HINT, GL_NICEST);
 
-    /* gray background */
-    glClearColor(0.5f, 0.5f, 0.5f, 1.0f);
-
-    /* original texture loading used to be here */
-
-    /* texture filtering, we modify default values since we don't have mipmaps */
-    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_WRAP_S, GL_CLAMP_TO_EDGE);
-    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+    /* multisampling for polygons, conflicts with *polygon* anti-aliasing */
+    glEnable(GL_MULTISAMPLE);
 
     /* how OpenGL combines the colors from texels with the color of the underlying
      * geometry is controlled by the texture environment mode */
     glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
 
     /* once texture is loaded and enabled, it will applied to every primitive
-     * that specifies coordinates */
+     * that specifies coordinates, ORLY? */
     glEnable(GL_TEXTURE_2D);
 
-    /* multisampling for polygons, conflicts with anti-aliasing */
-    //glEnable(GL_MULTISAMPLE);
-
     /* don't know about this, but why not */
     glLightModeli(GL_LIGHT_MODEL_COLOR_CONTROL, GL_SEPARATE_SPECULAR_COLOR);
+
+    /* gray background */
+    glClearColor(0.5f, 0.5f, 0.5f, 1.0f);
 }
 
 void setup_sdl(void)
diff --git a/sdl/pyramid.c b/sdl/pyramid.c
index d03b4ce..fc95fd6 100644
--- a/sdl/pyramid.c
+++ b/sdl/pyramid.c
@@ -33,6 +33,7 @@ static void process_events(void);
 static void platform_init(void);
 static void platform_destroy(void);
 static void render(void);
+GLuint gltLoadTGATexture(const char *);
 
 /* global */
 int program_running = 1;
@@ -51,6 +52,9 @@ static struct
     GLuint ground_list;
     GLuint triangle_list;
 
+    /* pyramid texture handle */
+    GLuint textures[2];
+
     GLfloat xrot;
     GLfloat yrot;
 } p;
@@ -150,44 +154,73 @@ static void process_events(void)
         flag = !flag;
 }
 
-static void platform_init(void)
+/* mipmapping enabled by default */
+GLuint gltLoadTGATexture(const char *fname)
 {
+    GLuint handle;
+
     /* variables used for texture loading */
     GLbyte *pBytes;
     GLint iWidth, iHeight, iComponents;
     GLenum eFormat;
 
-    /* set the camera to <0,0,0> */
-    glframe_reset(&p.camera);
-    p.xrot = 0;
-    p.yrot = 0;
+    glGenTextures(1, &handle);
+    glBindTexture(GL_TEXTURE_2D, handle);
 
     /* load texture */
+	glTexParameteri(GL_TEXTURE_2D, GL_GENERATE_MIPMAP, GL_TRUE);
     glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
-    pBytes = gltLoadTGA("stone.tga", &iWidth, &iHeight, &iComponents, &eFormat);
+
+    pBytes = gltLoadTGA(fname, &iWidth, &iHeight, &iComponents, &eFormat);
     if (!pBytes)
         fprintf(stderr, "gltLoadTGA: failed to load texture!\n");
 
-    /* load texture image */
     glTexImage2D(GL_TEXTURE_2D, 0, iComponents, iWidth, iHeight, 0, eFormat,
                  GL_UNSIGNED_BYTE, pBytes);
     free(pBytes);
 
+    /* seems like mipmapping only applies to MIN_FILTER since mipmapping divides
+     * current texture into smaller and smaller pieces
+     */
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR); /* GL_LINEAR to disable mipmapping */
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+
+    return handle;
+}
+
+static void platform_init(void)
+{
+    memset(&p, 0, sizeof(p));
+
+    /* set the camera to <0,0,0> */
+    glframe_reset(&p.camera);
+    p.textures[0] = gltLoadTGATexture("stone.tga");
+    p.textures[1] = gltLoadTGATexture("grass.tga");
+
     /* display list, precompile commands */
     p.ground_list = glGenLists(2);
     p.triangle_list = p.ground_list + 1;
 
+    /* a ground with grass drawn using magneta lines */
     glNewList(p.ground_list, GL_COMPILE);
+       //glBindTexture(GL_TEXTURE_2D, p.textures[1]);
+       glColor3ub(255, 0, 255);
        gltDrawGround();
     glEndList();
 
+    /* a triangle with a texture */
     glNewList(p.triangle_list, GL_COMPILE);
+       glBindTexture(GL_TEXTURE_2D, p.textures[0]);
+       glColor3f(1.0f, 1.0f, 1.0f);
        gltDrawTriangle();
     glEndList();
 }
 
 static void platform_destroy(void)
 {
+    glDeleteTextures(2, p.textures);
     glDeleteLists(p.ground_list, 2);
 }
 
@@ -199,8 +232,8 @@ static void render(void)
     /* save the matrix state and do the rotations */
     glPushMatrix();
         /* apply camera transform, and draw the ground */
-        glframe_apply_camera_transform(&p.camera, 0);
-        glColor3ub(255, 0, 255);
+        glframe_apply_camera_transform(&p.camera, 1);
+
         glCallList(p.ground_list);
 
         glPushMatrix();
@@ -210,7 +243,6 @@ static void render(void)
         glRotatef(p.yrot, 0.0f, 1.0f, 0.0f);
 
         /* draw the pyramid */
-        glColor3f(1.0f, 1.0f, 1.0f);
         glCallList(p.triangle_list);
         glPopMatrix();