opengl_learn

commit 3b05886e88115096fb40a21deebc099c7e255b97
parent 2a9099b38c262d371fa9bba3db2de94f9b61dbf1
Author: David DiPaola <DavidDiPaola@users.noreply.github.com>
Date:   Fri,  5 Oct 2018 20:22:40 -0400

05: added translation transform
05: fixed window title text

Diffstat:
M
05-geometrytransforms.c
 | 
12
+++++++-----
M
ogl/Makefile
 | 
2
+-
M
ogl/ogl.h
 | 
6
++++++
A
ogl/ogl_mat4f_translate.c
 | 
23
+++++++++++++++++++++++

4 files changed, 37 insertions(+), 6 deletions(-)
diff --git a/05-geometrytransforms.c b/05-geometrytransforms.c
@@ -23,7 +23,7 @@ licensed under CC0 (public domain, see https://creativecommons.org/publicdomain/
 
 int
 main() {
-	GLFWwindow * window = ogl_init(400, 240, "03 - texture");
+	GLFWwindow * window = ogl_init(400, 240, "05 - geometry transforms");
 
 	/* vu: vertex shader uniform,  va: vertex shader attribute,  fu: fragment shader uniform,  fv: fragment shader varying */
 	const char * program_vertex_source =
@@ -87,11 +87,13 @@ main() {
 	ogl_lookat(MVP_view_eye, MVP_view_center, MVP_view_up, &MVP_view);
 
 	struct ogl_mat4f MVP_model;
-	struct ogl_vec3f MVP_model_scale = { .x= 2.0f,  .y= 2.0f,  .z= 2.0f };
-	ogl_mat4f_identity(&MVP_model);
-	/* TODO model translation */
+	struct ogl_vec3f MVP_model_translation = { .x= 0.0f,  .y= 0.0f,  .z=-1.0f };
 	/* TODO model rotation */
-	ogl_mat4f_scale(MVP_model, MVP_model_scale, &MVP_model);
+	struct ogl_vec3f MVP_model_scale       = { .x= 2.0f,  .y= 2.0f,  .z= 2.0f };
+	ogl_mat4f_identity( &MVP_model);
+	ogl_mat4f_translate(MVP_model, MVP_model_translation, &MVP_model);
+	/* TODO model rotation */
+	ogl_mat4f_scale(    MVP_model, MVP_model_scale,       &MVP_model);
 
 	struct ogl_mat4f MVP;
 	ogl_mat4f_identity(&MVP);
diff --git a/ogl/Makefile b/ogl/Makefile
@@ -1,7 +1,7 @@
 SRC = \
 	_ogl.c ogl_init.c \
 	ogl_GLfloat_isapproxequal.c ogl_GLfloat_print.c \
-	ogl_mat4f_identity.c ogl_mat4f_isapproxequal.c ogl_mat4f_multiply.c ogl_mat4f_print.c ogl_mat4f_scale.c \
+	ogl_mat4f_identity.c ogl_mat4f_isapproxequal.c ogl_mat4f_multiply.c ogl_mat4f_print.c ogl_mat4f_scale.c ogl_mat4f_translate.c \
 	ogl_program_build.c ogl_program_uniform_get_ID.c ogl_program_uniform_set_mat4f.c \
 	ogl_vec3f_cross.c ogl_vec3f_dot.c ogl_vec3f_isapproxequal.c ogl_vec3f_magnitude.c ogl_vec3f_normal.c ogl_vec3f_print.c \
 	ogl_arraybuffer_load.c \
diff --git a/ogl/ogl.h b/ogl/ogl.h
@@ -89,6 +89,12 @@ ogl_mat4f_scale(
 	struct ogl_mat4f * out_result
 );
 
+void
+ogl_mat4f_translate(
+	struct ogl_mat4f matrix, struct ogl_vec3f translation,
+	struct ogl_mat4f * out_result
+);
+
 
 
 void
diff --git a/ogl/ogl_mat4f_translate.c b/ogl/ogl_mat4f_translate.c
@@ -0,0 +1,23 @@
+/*
+2018 David DiPaola
+licensed under CC0 (public domain, see https://creativecommons.org/publicdomain/zero/1.0/)
+*/
+
+#include "ogl.h"
+
+void
+ogl_mat4f_translate(
+	struct ogl_mat4f matrix, struct ogl_vec3f translation,
+	struct ogl_mat4f * out_result
+) {
+	/* see OpenGL 2.1 glTranslate(): https://www.khronos.org/registry/OpenGL-Refpages/gl2.1/xhtml/glTranslate.xml */
+
+	struct ogl_mat4f translation_matrix = { .values = {
+		1.0f, 0.0f, 0.0f, translation.x,
+		0.0f, 1.0f, 0.0f, translation.y,
+		0.0f, 0.0f, 1.0f, translation.z,
+		0.0f, 0.0f, 0.0f,          1.0f,
+	}};
+	ogl_mat4f_multiply(matrix, translation_matrix, out_result);
+}
+