implemented r_glsl_water cvar (refraction and reflection rendering)

[xonotic/darkplaces.git] / gl_backend.c

diff --git a/gl_backend.c b/gl_backend.c
index f4c81f636542af3bd5bab20acec462987328ea34..7daeff35e9586ac7b3a78735ed514eac55bb8b8a 100644 (file)
--- a/gl_backend.c
+++ b/gl_backend.c
@@ -14,7 +14,7 @@ cvar_t gl_polyblend = {CVAR_SAVE, "gl_polyblend", "1", "tints view while underwa
 cvar_t gl_dither = {CVAR_SAVE, "gl_dither", "1", "enables OpenGL dithering (16bit looks bad with this off)"};
 cvar_t gl_lockarrays = {0, "gl_lockarrays", "0", "enables use of glLockArraysEXT, may cause glitches with some broken drivers, and may be slower than normal"};
 cvar_t gl_lockarrays_minimumvertices = {0, "gl_lockarrays_minimumvertices", "1", "minimum number of vertices required for use of glLockArraysEXT, setting this too low may reduce performance"};
-cvar_t gl_vbo = {0, "gl_vbo", "1", "make use of GL_ARB_vertex_buffer_object extension to store static geometry in video memory for faster rendering"};
+cvar_t gl_vbo = {CVAR_SAVE, "gl_vbo", "1", "make use of GL_ARB_vertex_buffer_object extension to store static geometry in video memory for faster rendering"};
 
 cvar_t v_flipped = {0, "v_flipped", "0", "mirror the screen (poor man's left handed mode)"};
 qboolean v_flipped_state = false;
@@ -282,7 +282,7 @@ void GL_SetupView_Orientation_Identity (void)
 void GL_SetupView_Orientation_FromEntity(const matrix4x4_t *matrix)
 {
        matrix4x4_t tempmatrix, basematrix;
-       Matrix4x4_Invert_Simple(&tempmatrix, matrix);
+       Matrix4x4_Invert_Full(&tempmatrix, matrix);
        Matrix4x4_CreateRotate(&basematrix, -90, 1, 0, 0);
        Matrix4x4_ConcatRotate(&basematrix, 90, 0, 0, 1);
        Matrix4x4_Concat(&backend_viewmatrix, &basematrix, &tempmatrix);
@@ -368,6 +368,65 @@ void GL_SetupView_Mode_Ortho (double x1, double y1, double x2, double y2, double
        CHECKGLERROR
 }
 
+void GL_SetupView_ApplyCustomNearClipPlane(double normalx, double normaly, double normalz, double dist)
+{
+       double matrix[16];
+       double q[4];
+       double d;
+       float clipPlane[4], v3[3], v4[3];
+       float normal[3];
+
+       // This is Olique Depth Projection from http://www.terathon.com/code/oblique.php
+       // modified to fit in this codebase.
+
+       VectorSet(normal, normalx, normaly, normalz);
+       Matrix4x4_Transform3x3(&backend_viewmatrix, normal, clipPlane);
+       VectorScale(normal, dist, v3);
+       Matrix4x4_Transform(&backend_viewmatrix, v3, v4);
+       // FIXME: LordHavoc: I think this can be done more efficiently somehow but I can't remember the technique
+       clipPlane[3] = -DotProduct(v4, clipPlane);
+
+#if 0
+{
+       // testing code for comparing results
+       float clipPlane2[4];
+       VectorCopy4(clipPlane, clipPlane2);
+       R_Mesh_Matrix(&identitymatrix);
+       VectorSet(q, normal[0], normal[1], normal[2], -dist);
+       qglClipPlane(GL_CLIP_PLANE0, q);
+       qglGetClipPlane(GL_CLIP_PLANE0, q);
+       VectorCopy4(q, clipPlane);
+}
+#endif
+
+       // Calculate the clip-space corner point opposite the clipping plane
+       // as (sgn(clipPlane.x), sgn(clipPlane.y), 1, 1) and
+       // transform it into camera space by multiplying it
+       // by the inverse of the projection matrix
+       Matrix4x4_ToArrayDoubleGL(&backend_projectmatrix, matrix);
+
+       q[0] = ((clipPlane[0] < 0.0f ? -1.0f : clipPlane[0] > 0.0f ? 1.0f : 0.0f) + matrix[8]) / matrix[0];
+       q[1] = ((clipPlane[1] < 0.0f ? -1.0f : clipPlane[1] > 0.0f ? 1.0f : 0.0f) + matrix[9]) / matrix[5];
+       q[2] = -1.0f;
+       q[3] = (1.0f + matrix[10]) / matrix[14];
+
+       // Calculate the scaled plane vector
+       d = 2.0f / DotProduct4(clipPlane, q);
+
+       // Replace the third row of the projection matrix
+       matrix[2] = clipPlane[0] * d;
+       matrix[6] = clipPlane[1] * d;
+       matrix[10] = clipPlane[2] * d + 1.0f;
+       matrix[14] = clipPlane[3] * d;
+
+       // Load it back into OpenGL
+       qglMatrixMode(GL_PROJECTION);CHECKGLERROR
+       qglLoadMatrixd(matrix);CHECKGLERROR
+       qglMatrixMode(GL_MODELVIEW);CHECKGLERROR
+       CHECKGLERROR
+       Matrix4x4_FromArrayDoubleGL(&backend_projectmatrix, matrix);
+}
+
 typedef struct gltextureunit_s
 {
        const void *pointer_texcoord;