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first lighting attempt; specular not working

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This commit is contained in:
Josh Holtrop 2011-05-01 08:34:13 -04:00
parent 4e40f6af5c
commit 8bd56f42aa
3 changed files with 48 additions and 10 deletions
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28
lighting/f_shader.glsl
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@ -1,5 +1,31 @@
varying vec3 eye_pos_i;
varying vec3 normal_i;
varying vec4 diffuse_i;
void main(void) void main(void)
{ {
gl_FragColor = gl_Color; vec3 n, lightDir;
vec4 color;
float NdotL, RdotEye;
lightDir = vec3(-0.1, 0, -0.9);
color = vec4(0.2, 0.2, 0.2, 1.0); /* ambient light */
n = normalize(normal_i);
NdotL = max(dot(n, -lightDir), 0.0);
if (NdotL > 0.0)
{
/* diffuse component */
color += diffuse_i * NdotL;
/* specular component */
RdotEye = dot(normalize(eye_pos_i), normalize(reflect(-lightDir, n)));
if (RdotEye > 0.0)
{
color += pow(RdotEye, 96.5);
}
}
gl_FragColor = color;
} }

21
lighting/test.cc
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@ -15,13 +15,13 @@ using namespace std;
#define STRIDE(a, b) ((unsigned long)(b) - (unsigned long)(a)) #define STRIDE(a, b) ((unsigned long)(b) - (unsigned long)(a))
#define OFFSET(a, b) ((const GLvoid *)STRIDE((a), (b))) #define OFFSET(a, b) ((const GLvoid *)STRIDE((a), (b)))
const GLfloat data[][2][3] = { const GLfloat data[][3][3] = {
{{-1.0, -0.6, 0.0}, {1, 0, 0}}, {{-1.0, -0.6, 0.0}, {1, 0, 0}, {0, 0, 1}},
{{-0.2, -0.6, 0.0}, {0, 1, 0}}, {{-0.2, -0.6, 0.0}, {0, 1, 0}, {0, 0, 1}},
{{-0.6, 0.6, 0.0}, {0, 0, 1}}, {{-0.6, 0.6, 0.0}, {0, 0, 1}, {0, 0, 1}},
{{0.2, -0.6, 0.0}, {1, 0, 0}}, {{0.2, -0.6, 0.0}, {1, 0, 0}, {0, 0.7071, 0.7071}},
{{1.0, -0.6, 0.0}, {0, 1, 0}}, {{1.0, -0.6, 0.0}, {0, 1, 0}, {0, 0.7071, 0.7071}},
{{0.6, 0.6, -10.0}, {0, 0, 1}} {{0.6, 0.6, -10.0}, {0, 0, 1}, {0, 0.7071, 0.7071}}
}; };
const GLushort indices[] = { const GLushort indices[] = {
0, 1, 2, 3, 4, 5 0, 1, 2, 3, 4, 5
@ -29,7 +29,8 @@ const GLushort indices[] = {
GLuint program, vs, fs, data_vbo, index_vbo; GLuint program, vs, fs, data_vbo, index_vbo;
enum Locations { enum Locations {
LOC_POSITION, LOC_POSITION,
LOC_COLOR LOC_COLOR,
LOC_NORMAL
}; };
char * loadFile(const char *fname) char * loadFile(const char *fname)
@ -154,6 +155,7 @@ bool init(int width, int height)
glBindAttribLocation(program, LOC_POSITION, "pos"); glBindAttribLocation(program, LOC_POSITION, "pos");
glBindAttribLocation(program, LOC_COLOR, "color"); glBindAttribLocation(program, LOC_COLOR, "color");
glBindAttribLocation(program, LOC_NORMAL, "normal");
glLinkProgram(program); glLinkProgram(program);
@ -183,10 +185,13 @@ void display(void)
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, index_vbo); glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, index_vbo);
glEnableVertexAttribArray(LOC_POSITION); glEnableVertexAttribArray(LOC_POSITION);
glEnableVertexAttribArray(LOC_COLOR); glEnableVertexAttribArray(LOC_COLOR);
glEnableVertexAttribArray(LOC_NORMAL);
glVertexAttribPointer(LOC_POSITION, 3, GL_FLOAT, GL_FALSE, glVertexAttribPointer(LOC_POSITION, 3, GL_FLOAT, GL_FALSE,
STRIDE(&data[0], &data[1]), OFFSET(&data[0], &data[0][0])); STRIDE(&data[0], &data[1]), OFFSET(&data[0], &data[0][0]));
glVertexAttribPointer(LOC_COLOR, 3, GL_FLOAT, GL_FALSE, glVertexAttribPointer(LOC_COLOR, 3, GL_FLOAT, GL_FALSE,
STRIDE(&data[0], &data[1]), OFFSET(&data[0], &data[0][1])); STRIDE(&data[0], &data[1]), OFFSET(&data[0], &data[0][1]));
glVertexAttribPointer(LOC_NORMAL, 3, GL_FLOAT, GL_FALSE,
STRIDE(&data[0], &data[1]), OFFSET(&data[0], &data[0][2]));
glDrawElements(GL_TRIANGLES, sizeof(indices)/sizeof(indices[0]), glDrawElements(GL_TRIANGLES, sizeof(indices)/sizeof(indices[0]),
GL_UNSIGNED_SHORT, OFFSET(&indices, &indices[0])); GL_UNSIGNED_SHORT, OFFSET(&indices, &indices[0]));
SDL_GL_SwapBuffers(); SDL_GL_SwapBuffers();

9
lighting/v_shader.glsl
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@ -1,9 +1,16 @@
attribute vec3 pos; attribute vec3 pos;
attribute vec3 color; attribute vec3 color;
attribute vec3 normal;
varying vec3 eye_pos_i;
varying vec3 normal_i;
varying vec4 diffuse_i;
void main(void) void main(void)
{ {
gl_Position = gl_ModelViewProjectionMatrix * vec4(pos, 1); gl_Position = gl_ModelViewProjectionMatrix * vec4(pos, 1);
gl_FrontColor = vec4(color, 1); eye_pos_i = vec3(gl_Position.x, gl_Position.y, gl_Position.z);
normal_i = gl_NormalMatrix * normal;
diffuse_i = vec4(color, 1);
} }